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Garden Soil Preparation - It's Not Too Late

11/9/2017

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Autumn is an excellent time to add organic materials and till garden soils. Winter can still be a good time to take care of this chore as long as the soil isn’t frozen. It is far wiser to till now than to wait until spring when cold, wet conditions can limit your ability to work soils easily. Working soil when it is wet destroys soil structure and results in hard clods that are very slow to break down. On the other hand, dry soil may need to be watered so it can be more easily tilled. Be sure to wait several days after watering to let soil moisture levels moderate. You want the soil moist, not wet or dry, when tilling. 
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There is a limit to how much organic material such as leaves can be added in one application. Normally, a layer 2 inches deep is adequate with 5 to 6 inches being the maximum that can be added at one time. Shredding the material before application encourages faster and more complete decomposition due to increased surface area. Remember, soil preparation is an important key to a successful garden. (Ward Upham)

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Miscellaneous: Compost pH

3/20/2017

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Many gardeners assume that compost is acidic but such is usually not the case.  Compost is more often alkaline than acidic.  The possible use of alkaline composts on highbush blueberries was enough of a problem that Oregon State University carried out a study that included determining the pH of various composts. The listing below is of some of the composts Oregon State University studied and the pH of those materials.  We have not listed those composted from materials not common in Kansas such as hops and mint hay.
 
Material                       pH
Mixed Manure                     7.9
Horse Manure                     6.4
Dairy Solids                          8.0
Leaf                                          7.2
Yard Debris                          7.7
Composted Bark                5.4

It is interesting to note the tremendous variability in pH; from 8.0 for dairy solids to 5.4 for composted bark. Therefore, it is important to perform a soil test on soils that have been heavily amended with compost as the compost may have affected the pH. (Ward Upham)

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Miscellaneous: Adding Organic Matter in the Spring

3/14/2017

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​Organic matter is a good way to improve garden soil as it improves a heavy soil by bettering tilth, aeration and how quickly the soil absorbs water.  However, organic matter added in the spring should be well decomposed and finely shredded/ground. Manures and compost should have a good earthy smell without a hint of ammonia. Add a 2-inch layer of organic matter to the surface of the soil and work the materials into the soil thoroughly. Be sure soils are dry enough to work before tilling as wet soils will produce clods.
 
To determine if a soil is too wet to work, grab a handful and squeeze. If water comes out, it is much too wet. Even if no water drips out, it still may not be dry enough to work. Push a finger into the soil you squeezed. If it crumbles, it is dry enough, but if your finger just leaves an indentation, more time is needed. Be sure to take your handfuls of soil from the depth you plan to work the soil because deeper soils may contain more moisture than the surface. (Ward Upham)

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Horticulture Newsletter 2017, No. 8

2/21/2017

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Video of the Week:
​Making Your Own Seed Tape

Vegetables:
Cure the Itch by Planting Peas

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If you are tired of winter and hunger for spring, try planting peas as soon as the soil dries and the soil temperature reaches 40 degrees. We have several types of peas we can plant in Kansas. Probably the most common is the shelling pea and the old standard in this group is Little Marvel. Though Little Marvel is still on our recommended list, we have a number of others that do well including Green Arrow, Knight, Maestro, Burpeeana and Mr. Big. All of these are early maturing types that allow us to harvest a crop before the hot weather arrives and stops production. Snow peas are those commonly used in stir-fry that have a crisp edible pod.
 
Recommended varieties include Dwarf Grey Sugar and Mammoth Melting Sugar. Sugar snap peas resemble shelling peas but have a thick, fleshy pod and can be eaten fresh, steamed or cooked. Like snow peas, they are not shelled but eaten pod and all. We recommend Sugar Bon, Sugar Ann, Super Sugar Snap and Sugar Sprint.
 
Peas should be planted shallow, about one-half inch deep, to encourage rapid germination and emergence. Seed in the row should be spaced 2 inches apart. Many people often plant two rows 6 to 8 inches apart so the floppy plants can support one another. For some older varieties, this may not be enough. They may need trellising to support the growing vines. Fencing may be needed to keep rabbits away. (Ward Upham)

Lettuce

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Though lettuce is most often planted directly from seed in late March to early April, it can be started from transplants. Transplants allow lettuce to mature earlier so that it escapes the excessive heat that can lead to a strong flavor and bitterness.
 
Seed should be started four to five weeks before transplanting. Because transplants are placed at the same time as direct seeding, now would be a good time to begin. Use a seed starting mix and plant shallow as lettuce requires light for germination. A soil media temperature of 60 to 68 degrees will encourage germination. Watch the media temperature carefully, as seed can enter a thermal dormancy if germination temperatures are excessive. Also, a cooler temperature of 55 to 60 degrees should be used once the plants emerge.
 
Time to maturity varies depending on the type of lettuce, with leaf lettuce being the quickest, followed by bibb, romaine, and buttercrunch lettuce. Head or crisphead lettuce is the slowest and is least likely to mature before becoming bitter.
 
Spacing also varies with type. Leaf lettuce plants are spaced 4 to 6 inches apart, buttercrunch, bibb, and romaine are set at 6 to 8 inches and head lettuce should be at least 8 inches apart in the row. Lettuce does not have an extensive root system and requires regular watering if rainfall is lacking.
 
Fertilize before planting according to soil test. Plants should also be sidedressed when about 1/3 grown. Sidedressing is done with fertilizers that have more nitrogen than phosphorus and potassium. Use 1/3 cup of nitrate of soda (16-0-0) or 1/4 cup of a 27-3-3, 29-5-4 or similar fertilizer per 10 feet of row. The latter fertilizers are lawn fertilizers but will work well for sidedressing as long as they do not contain weed killers or weed preventers. (Ward Upham)

Soil Temperature and Vegetables

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One of the most neglected tools for vegetable gardeners is a soil thermometer. Soil temperature is a much better measure of when to plant than air temperature or the calendar. Planting when soil is too cool can cause seeds to rot and transplants to sit there.
 
A number of vegetables can germinate and grow at cool temperatures. For example, peas will germinate and grow well at a soil temperature of 40 F. Though lettuce, parsnips, and spinach can sprout at a soil temperature of 35 F, they prefer at least 45 F for best germination and growth. Radishes also do well at a soil temperature of 45 F. Warm-season crops such as tomatoes, sweet corn and beans prefer at least 55 F for germination (or transplanting), but others such as peppers, cucumbers, melons and sweet potatoes need it even warmer, about 60 F.
 
Taking soil temperature accurately is a bit of a science. First, use a metal soil thermometer, which is sold in many garden, auto parts and hardware stores. Take temperature 2.5 inches deep at about 10 to 11 a.m. Temperature variations throughout the day and night affect soil temperature, with lowest readings after dawn and warmest around mid-afternoon. The late-morning reading gives a good average temperature. If taking the soil temperature at this time is not practical, take a reading before you leave for work and a second when you return home and use the average. Also be sure to get a consistent reading for four to five days in a row before planting, and make sure a cold snap is not predicted.
 
An excellent guide sheet on this subject is published by the Alabama Cooperative Extension System and is titled “Soil Temperature Conditions for Vegetable Seed Germination.” It can be found at http://www.aces.edu/pubs/docs/A/ANR-1061/ANR-1061.pdf   (Ward Upham)

Ornamentals:
Forcing Stems of Woody Plants for Indoor Blooms

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Stems of a number of woody plants can be forced into bloom for indoor display. Of course, some are easier to force than others. Three of the easiest are forsythia, pussywillow, and flowering quince. These plants have now gone through enough cold weather to satisfy their chilling requirement and should bloom if given the right conditions.
 
Remember that the flower buds on forsythia are killed as temperatures reach –10 degrees F. If your area has had temperatures this far below zero, use one of the other woody plants.
 
Choose a day that is above freezing for collecting branches for blooming. Keep the stem length to 3 feet or less. As you cut, place the stems in a bucket of water. Once you have the number of branches you want, bring them into the house and soak them in warm water for several hours -- a bathtub works well for this. This ensures that the stems and buds are fully hydrated. Next, place them in a container that has a warm, preservative solution and place them in an environment with high humidity and plenty of light.
 
Make your preservative solution by dissolving packets of floral preservative in water. These packets can often be obtained from your local florist. You can also make your own preservative by adding a tablespoon of Listerine per gallon of water, but commercial preservatives are preferred. Floral preservatives accomplish two functions; they prevent bacterial growth in your water and provide nutrients and energy for the life processes of the plants.

Many times our houses have a very low relative humidity during the winter. These low humidities can lead to dehydration of flower buds and blossoms. To raise the humidity around your plants, mist the plants or drape a dry cleaner's bag over your stems. If a cleaner's bag is too small, use a painter’s clear plastic drop cloth. Humidifiers can also help raise humidity levels. Normally, forsythia will take about nine days to flower, quince will require between 12 to 20, and pussywillow needs from five to 15 days. The time required will vary depending on indoor conditions and how late in the winter the branches were collected. Most woody plants should be in flower within three weeks of collection and will remain in flower for about a week before blooms start to fade.  (Ward Upham)

Pruning Deciduous Shrubs

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Gardeners are eager to get out and do something in the landscape this time of year. One chore that can be taken care of now is pruning certain shrubs. Often, gardeners approach pruning with trepidation, but it is not as difficult as it may seem. Remember, not all shrubs need to be pruned (i.e., witch hazel), and certain shrubs, which will be identified later, should not be pruned this time of year. Shrubs are pruned to maintain or reduce size, rejuvenate growth, or to remove diseased, dead or damaged branches. Deciduous shrubs are those that lose their leaves each winter. Evergreen shrubs maintain foliage all year and include yews and junipers.
 
Deciduous shrubs are placed into three groups:
- Those that flower in the spring on wood produced last year;
- Those that flower later in the year on current seasons’ growth; and
- Those that may produce flowers, but those flowers are of little ornamental value.

Shrubs that flower in the spring should not be pruned until immediately after flowering. Though pruning earlier will not harm the health of the plant, the flowering display will be reduced. Examples of these types of plants include forsythia, lilac and mock orange. Shrubs that bloom on current seasons’ growth or that do not produce ornamental flowers are best pruned in late winter to early spring. Examples include Rose-of-Sharon, pyracantha, Bumald spirea and Japanese spirea.
 
Pruning during the spring allows wounds to heal quickly without threat from insects or disease. There is no need to treat pruning cuts with paints or sealers. In fact, some of these products may retard healing. There are three basic methods used in pruning shrubs: thinning, heading back and rejuvenating. Thinning is used to thin out branches from a shrub that is too dense. It is accomplished by removing most of the inward growing twigs by either cutting them back to a larger branch or cutting them back to just above an outward- facing bud. On multi-stemmed shrubs, the oldest canes may be completely removed.
 
Heading back is done by removing the end of a branch by cutting it back to a bud and is used for either reducing height or keeping a shrub compact. Branches are not cut back to a uniform height because this results in a "witches-broom" effect.
 
Rejuvenation is the most severe type of pruning and may be used on multi-stem shrubs that have become too large, with too many old branches to justify saving the younger canes. All stems are cut back to 3- to 5-inch stubs. This is not recommended for all shrubs but does work well for spirea, forsythia, pyracantha, ninebark, Russian almond, little leaf mock orange, shrub roses and flowering quince. (Ward Upham)

Miscellaneous:
An Easy Way to Propagate Houseplants

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Houseplant growers don’t need a lot of equipment to propagate a houseplant. Gardeners can get by with a coffee cup, potting soil, 3 drinking straws, a plastic bag and a rubber band. Start by making a slit or hole in the bottom of the coffee cup so that it drains excess water. Then fill the cup with moist potting soil. Do not use garden soil as it does not drain well. Too much water (and too little oxygen) will harm cuttings.
 
Prepare the Cutting
- Remove about a 4-inch or smaller piece from the tip of the plant. The cut should be made just below a node. A node is where a leaf attaches to the stem.
- Remove the leaf or leaves from the bottom node. This is where roots will form.
- If there are just a few leaves on the tip, fine. However, if there is a cluster of leaves, remove most of them below the tip. This will cut down on water loss as the plant makes new roots.
 
Plant the Cutting
- Push the bottom end of the cutting into the soil. The remaining leaves should not contact the soil. A rooting hormone may be used if desired but usually is unnecessary with houseplants.
 
Make a Greenhouse
- Place 3 straws equidistant from each other near the outside edge the cup full of potting soil. They will support the plastic bag so that it does not contact the leaves and cause them to rot.
- Place the plastic bag over the cup like a tent and use the rubber band to secure the open end of the bag to the sides of the cup.
 
Grow the Cutting
- Place the cutting in bright, indirect light. Do not place in full sunlight as the cutting may overheat.
- Keep the cutting warm. A temperature of 72 degrees is ideal. Roots should form in about 10 days. Check by removing the plastic bag and pulling gently on the cutting. If it doesn’t pull out easily, roots have started to form and the plastic bag can be left off. (Ward Upham)

Leaching Houseplants

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Everyone knows that someone stranded in the ocean should not drink the water. The salt content of that water will make a bad situation worse.  What many people don’t realize is that this same principle can harm plants.
 
Fertilizers are salts. They must be salts in order for the plant roots to take them up. However, salt levels can build up over time and eventually may harm plant roots leading to scorched leaves and unhealthy plants. Though this can happen under field conditions, especially in low rainfall areas, it is particularly critical with houseplants.
 
Houseplants have a certain soil volume that doesn’t change until a plant is repotted. Salt build-up can be a crucial concern especially if plants are fertilized heavily. Leaching an overabundance of salts can be an important practice to ensure the health of our houseplants. Leaching is not a complicated or difficult process. It consists of adding enough water to wash out excess salts.
 
How much water is enough? Add the amount of water that would equal twice the volume of the pot. This, of course, would need to be done outside or in a bathtub or sink. Water must be added slowly so that it doesn’t overflow the rim of the pot. If salt has formed a crust on the surface of the soil, remove it but don’t take more than 1/4 inch of the underlying media. This may also be a good time to repot the plant. (Ward Upham)
 
Contributors: Ward Upham, Extension

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Horticulture Newsletter 2017, No.7

2/14/2017

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Video of the Week:
How to Make a Grow Light

Turfgrass:
Lawn Calendar for Cool-Season Grasses

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The following suggestions are for cool-season grasses such as Kentucky bluegrass or tall fescue. Zoysiagrass, bermudagrass, and buffalograss are warm-season grasses and require a different maintenance regime. A warm-season grass calendar will be covered in a later newsletter.
 
March
Spot treat broadleaf weeds if necessary. Treat on a day that is 50 degrees or warmer. Rain or irrigation within 24 hours of application will reduce effectiveness.
 
April
Apply crabgrass preventer when redbud trees are in full bloom, usually in April. The preventer needs to be watered in before it will start to work. One-quarter inch of water will be enough to water in any of the products mentioned in this calendar. Remember that a good, thick lawn is the best weed prevention and may be all that is needed.
 
May
Fertilize with a slow-release fertilizer if you water your lawn or if you normally receive enough rainfall that your turf doesn’t go drought-dormant during the summer. If there are broadleaf weeds, spot treat with a spray or use a fertilizer that includes a weed killer. Rain or irrigation within 24 hours of application will reduce effectiveness of the weed killer, but the fertilizer needs to be watered in. If you are using a product that has both fertilizer and weed killer, wait 24 hours after application before watering in.
 
June through Mid-July
Apply second round of crabgrass preventer by June 15 – unless you have used Dimension (dithiopyr) or Barricade (prodiamine) for the April application. These two products normally provide season-long control with a single application. Remember to water it in. If grubs have

been a problem in the past, apply a product containing imidacloprid during the first half of July. This works to prevent grub damage. It must be watered in before it becomes active.
 
Late-July through August
If you see grub damage, apply a grub killer that contains Dylox. Imidacloprid is effective against young grubs but may not be effective on late instar grubs. The grub killer containing Dylox must be watered in within 24 hours or effectiveness drops.
 
September
Fertilize around Labor Day. This is the most important fertilization of the year. Water in the fertilizer.
 
November
Fertilize. This fertilizer is taken up by the roots but is not used until the following spring. Water in fertilizer. Spray for broadleaf weeds even if they are small. Broadleaf weeds are much easier to control in the fall than in the spring. Spray on a day that is at least 50 degrees. Rain or irrigation within 24 hours reduces effectiveness. Use label rates for all products! (Ward Upham)

Vegetables:
Planting Asparagus

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Though it is too early to plant asparagus, it is not too early to make plans and prepare soil. This crop is a perennial and will survive for many years if given proper care. It prefers full sun and a well-drained soil and is usually placed on the edge of the garden area so that there is no need to till around the area to plant other crops.
 
Proper soil prep is especially important for perennial crops. Take a soil test to ensure proper levels of nutrients. See the accompanying article on how to take a soil test for the correct procedure.

Work the soil as early in the spring as possible but do not work wet soil as clods will form. Then add two inches of organic matter to the surface and the fertilizer and work again so the organic matter and fertilizer are blended into the soil.
 
Asparagus can be propagated from seed but is more often started from 1-year-old crowns. These crowns are planted deeply; about 8 inches deep either in a hole for each crown or in a trench. Space plants 18 to 24 inches apart. Fill in the trench gradually over the growing season to encourage growth.
 
March 15 to April 15 is the best planting time. Adapted varieties include Jersey Giant, Jersey King, Jersey Knight, Jersey Supreme and Purple Passion. These are all male hybrids that will produce three times as much as our old Martha or Mary Washington varieties.  Males have a number of advantages over females in that they live longer, emerge earlier in the spring, are more productive and eliminate potential volunteer plants that can reduce the productivity of a planting.
 
Weed control is very important. Competition with weeds results in slow establishment. A shallow hoeing should be all that is needed. (Ward Upham)

Gardening Calendar

The Kansas Healthy Yards website has a gardening calendar that many gardeners find helpful.  It lists all the months of the year and the chores that can be done during that month.  Each month is divided into separate sections such as Vegetables and Fruits, Flowers, Lawns, Trees and Shrubs and Houseplants. Not all suggestions will be helpful each year but are important to have included.  For example, one of the January tips is on removing snow and ice on limbs.  You may brush off the snow, if desired, but ice should be allowed to melt naturally.
 
To find the gardening calendar, go to  http://kansashealthyyards.org/ and click on “Gardening Calendar” in the gray bar at the top of the page.  (Ward Upham)

Flowers:
Fertilizing Spring-flowering Bulbs

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The best time to fertilize spring-flowering bulbs is when foliage emerges in the spring rather than at flowering. Traditionally, gardeners have applied fertilizer during bloom or a bit after, but because bulb roots start to die at flowering, fertilizer applied at bloom is wasted. Roots are active when the foliage first pokes through the ground. Nutrients applied then help the plant produce flowers the following year.

If bulbs have been fertilized in the past, there is often plenty of phosphorus and potassium in the soil. It is best to use a soil test to be certain. If the soil needs phosphorus and potassium, use a complete fertilizer (such as 10-10-10, 9-9-6, etc.) at the rate of 2.5 lbs. per 100 square feet. This would equal 1 rounded teaspoon per square foot. If phosphorus and potassium are not needed, blood meal makes an excellent fertilizer. It should be applied at the rate of 2 lbs. per 100 square feet or 1 teaspoon per square foot. Lawn fertilizers such as a 27-3-3 or 30-3-3 can be used, but cut the rate by a third. Also make sure the lawn fertilizer does not contain a weed preventer or weed killer.
 
Remember to leave the foliage until it dies naturally. The energy in the foliage is transferred to the bulb as the foliage dies and will help bloom next year. (Ward Upham)

Miscellaneous:
Soil Testing

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Most gardeners think that soil tests are done only to find out what nutrients are deficient. However, it is just as important to know if you have adequate levels of nutrients so you don't add unneeded fertilizer. The most basic soil test checks pH and the levels of phosphorus and potassium. Most of the lawn and garden soil tests that come out of our soil-testing lab show more than adequate levels of both phosphorus and potassium. If those nutrients are not needed, applying them is a waste of money and can be a source of pollution. In extreme cases, excess phosphorus can interfere with the uptake of micronutrients. So, if you haven't taken a soil test in several years, take one this spring.
 
Begin by taking a representative sample from a number of locations in the garden or lawn that goes from the surface to 6 to 8 inches deep. Mix the samples together in a clean container and select about 1 pint of soil. For more detail on taking a soil test, click here.
 
Take the soil to your local K-State Research and Extension office to have tests done at the K-State soil-testing laboratory for a small fee. A soil test determines fertility problems, not other conditions that may exist such as poor drainage, poor soil structure, soil borne diseases or insects, chemical contaminants or damage, or shade with root competition from other plants. All of these conditions may reduce plant performance but cannot be evaluated by a soil test. (Ward Upham)

Soil Test When Soils are Wet

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In many parts of the state, this would be a good problem to have. So let’s say you just had a rain and need to take a soil test. It would be best to wait until the soil dries but it is possible to take soil tests when soils are wet though there are precautions.
 
Soil samples should be air-dried before being submitted for testing. Do NOT use artificial means of drying such as an oven or microwave as such treatment may result in inaccurate readings of nutrient levels. Also, be sure to use a clean container to collect the sample. Wet samples are more likely to absorb foreign materials adhering to the container, which may also influence soil test results.
 
For information on how to take a soil sample, click here.
 
Take the sample into your local extension office. If you don’t know the address for your local, county extension office, see http://www.ksre.ksu.edu/Map.aspx   (Ward Upham)

Contributors: Ward Upham, Extension Associate

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Horticulture Newsletter 2016, No. 46

11/15/2016

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Video of the Week:

Upcoming Events:

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Kansas Turfgrass Conference in conjunction with KNLA

Mark the date to attend the Kansas Turfgrass Conference in conjunction with KNLA on December 6, 7 & 8 in Topeka.
 
The conference is an excellent way to learn about turf, nursery and landscape management, visit with old friends, network with new ones, and see all the latest equipment and supplies from local and national vendors.
 
The conference has been approved for Commercial pesticide recertification hours:
1 Core hour       3A - 8 hrs           3B - 9 hrs
 
International Society of Arboriculture CEUs and GCSAA education points will also be available by attending the conference.
 
Take advantage of the discounted preregistration rate and register by November 22! Download a copy of the program, get exhibitor information, or register online  http://2016ktf.eventbrite.com

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Great Plains Growers Conference
January 12, 13 & 14, 2017
St. Joseph, MO
For more information, go to http://www.greatplainsgrowersconference.org/

Fruit:
Reproducing Apple Trees

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Every so often we receive a question about how to make apple seeds germinate. Often, the person is looking for a way to reproduce an apple tree that is dying. Unfortunately, apple trees do not come true from seed. In other words, the apple seed produces trees that differ from the parent. It is extremely unlikely that any apple produced from seed will bear quality fruit. About 1 in every 80,000 apple seedlings will produce commercial quality fruit.
 
So, how do you reproduce an apple that is like the parent? The most common way is by grafting. Grafting is a procedure that joins two plants together. The upper part (or scion) becomes the top part of the tree, while the lower part (or stock) provides the root system or part of the trunk. In apples, the rootstock is often used to dwarf the tree so it is easier to prune, spray and harvest.
 
Apples are relatively easy to graft. How to graft is beyond the scope of this newsletter, but local libraries should have materials that cover the procedure, or you can find an excellent publication on the web at  http://muextension.missouri.edu/explorepdf/agguides/hort/g06971.pdf  (Ward Upham)

Miscellaneous:
Garden Soil Preparation - It's Not Too Late

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Autumn is an excellent time to add organic materials and till garden soils. Winter can still be a good time to take care of this chore as long as the soil isn’t frozen. It is far wiser to till now than to wait until spring when cold, wet conditions can limit your ability to work soils easily. Working soil when it is wet destroys soil structure and results in hard clods that are very slow to break down. On the other hand, dry soil may need to be watered so it can be more easily tilled. Be sure to wait several days after watering to let soil moisture levels moderate. You want the soil moist, not wet or dry, when tilling.
 
There is a limit to how much organic material such as leaves can be added in one application. Normally, a layer 2 inches deep is adequate with 5 to 6 inches being the maximum that can be added at one time. Shredding the material before application encourages faster and more complete decomposition due to increased surface area. Remember, soil preparation is an important key to a successful garden. (Ward Upham)

High pH Soils and What to Do With Them 

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Though there are high pH soils in most parts of the state, alkaline soils tend to be more common in the central and western regions of Kansas. These high pH soils can cause problems for plants by reducing the availability of certain micronutrients. For example, most Kansas soils have more than adequate amounts of iron. However, a high pH can make iron unavailable resulting in a condition known as iron chlorosis. Iron chlorosis reduces the health of plants by reducing photosynthesis. Lowering the pH of such soils will eliminate iron chlorosis.
 
Now would be a good time to have a soil test done to see if your pH is too high. If so, sulfur can be added either now or in the spring to lower the pH. Different textures of soil require different amounts. A sandy soil needs 7 pounds of sulfur per 1,000 square feet to reduce pH one point. A loam soil needs 11 pounds and clay needs 17 pounds to do the same. For example, if you wished to lower pH from 8.5 to 6.5 on a loam soil, you would need 22 pounds of sulfur per 1,000 square feet.
 
So, what pH do we shoot for? For most plants, a pH between 6.0 and 7.0 is preferred. Unfortunately, adding sulfur to lower pH is not as clear-cut a solution as we would like. Here are some other factors to keep in mind.
 
Free calcium carbonate: Some soils have free calcium carbonate, actual particles of limestone mixed in the soil. These "calcareous" soils normally have a pH of 7.3 to 8.5, with 8.2 to 8.3 being most common. In order for us to lower the pH with sulfur, all free calcium carbonate must be neutralized first. A recent soil test showed 6.7 percent free calcium carbonate. One pound of sulfur is needed to neutralize three pounds of calcium carbonate. Assuming 80 pounds for a cubic foot of soil, you would need about 1.75 pounds of sulfur per square foot just to neutralize the free lime. Additional sulfur would be needed to lower pH. Adding this much sulfur to a soil at one time is not recommended.
 
Not all high pH soils are calcareous. Perform this simple test to see if your soil contains appreciable amounts of free lime. Apply one drop of vinegar to dry soil. A vigorous fizz usually means the soil contains at least 3 percent calcium carbonate. A mild fizz suggests a calcium carbonate of between 1 and 2 percent and a fizz that can only be heard suggests the soil has a calcium carbonate content less than 1 percent.
 
How sulfur works: Elemental sulfur does not lower pH directly. It must first be oxidized to the sulfate form with the result being sulfuric acid. The sulfuric acid produces hydrogen, which acidifies the soil and lowers pH. The oxidation takes place primarily through microbial activity.
 
Oxidation takes time: Microbial oxidation of elemental sulfur takes time and depends on:
- number of sulfur oxidizing bacteria present
- temperature (75-104 degrees optimum)
- moisture content of soil (too wet or too dry will slow down process)
- size of sulfur particles (the smaller the better)
 
A single sulfur application normally takes at least 2 years for most the sulfur to react and form sulfuric acid. This, of course, depends on the above factors. So, what do you do about calcareous soils? See the companion article in this week’s newsletter for specific recommendations. (Ward Upham)

Iron Chlorosis and Calcareous Soils

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Iron chlorosis due to high pH soils is a significant problem in Kansas. Though Kansas soils normally contain adequate amounts of iron, a high pH makes that iron unavailable to the plant. Iron plays a major role in the production of chlorophyll. Thus, a lack of iron reduces the amount of chlorophyll and results in yellowing of leaves. Iron chlorosis weakens, and in severe cases, may kill a susceptible plant.

A popular recommendation for high pH soils is adding sulfur to lower pH. This works well for many soils, but not those that are calcareous. Calcareous soils are those that contain actual particles of calcium carbonate (limestone). Calcareous soils can be difficult to practically impossible to acidify because the sulfur must neutralize all the free limestone before the pH is affected long term. In many cases you would need well over a pound of sulfur per square foot just to neutralize the free lime.
 
So, what do you do? That depends on the situation. With vegetable gardens and annual flowerbeds, work products into the soil during the time of year when there are no plants present. Oregon State University suggests mixing 5 pounds of sulfur per 100 square feet into the soil before planting. The idea is to form little pockets of acidity that result in enough iron availability for the plants during the year of application. Note that this must be done each year. Another possibility is to use iron chelates. Iron chelates hold the iron in such a way that the plant can get to it. However, not all iron chelates will work in high pH soils. For soils with a pH over 7.2, use a chelate that contains FeEDDHA (Ethylene diamine-N,N bis(2hydroxyphenylacetic acid)). This can be found in the products Sequestar 6% Iron Chelate WDG, Sequestrene 138 and Millers FerriPlus. Chelates can either be mixed into the soil at planting or sprayed on the foliage early in the season. Reapply as needed. (Ward Upham)

Why Do Houseplants Lose Leaves After Being Brought Inside?

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 ewly bought houseplants or those brought in from outside often lose their leaves. In order to understand why this occurs, we need to look at how these plants are grown and what the plant needs to do to adapt to its new environment. Houseplants are normally produced either under shade outdoors in southern states or in greenhouses. Also, many homeowners move their houseplants outside during the summer. Regardless, the plants receive much more sunlight than they do in an indoor environment. Research done in Florida in the late 1970s revealed that tropical plants grown under high light conditions produce "sun leaves" while those grown under low light conditions have "shade leaves." These leaf types differ structurally in that sun leaves have less chlorophyll (the substance that plants use to convert sunlight to energy) and the chlorophyll that is present is located deeper inside the leaf. Sun leaves also tend to be thick, small and numerous while shade leaves are more thin, larger, and fewer in number. When plants are moved from one light condition to another they need time to adjust. This process is known as acclimatization. If they are forced to acclimatize too quickly, they will drop their sun leaves and produce a new set of shade leaves. If the acclimatization process is slower and less drastic, the plant can convert their sun leaves to the shade leaves that do better under low light. If going from shade to sun, this process is reversed.
 
Some houseplants are acclimatized before they are sold but many are not. So how do we help our new houseplants or those moved inside acclimatize to their new home environment? Houseplants should start out in an area of the home that receives plenty of light and then gradually moved to their permanent, darker location. This process should take 4 to 8 weeks depending on the degree of difference in light levels between the initial and final location of the plant. Remember, plants need to be acclimatized whether they are moved from a sunny location to one that receives less light or from shade to sun. Understanding plant processes allows us to anticipate potential problems. Acclimatization gives our houseplants a greater  chance of retaining leaves and avoiding the stress of completely replacing them. (Ward Upham)

Contributors: Ward Upham, Extension Associate

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Horticulture Newsletter 2016, No. 41

10/11/2016

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Video of the Week:
Planting Bulbs for Spring Color

Upcoming Events:

2016 Fall Orchid Show from the Kansas Orchid Society, November 5 & 6 at Botanica, The Wichita Gardens

Ornamentals:
Pruning Trees and Shrubs in the Fall

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Though light pruning and removal of dead wood are fine this time of year, more severe pruning should be left until spring. Consider pruning to be “light” if 10% of less of the plant is removed. Dead wood does not count in this calculation. Keep in mind that even light pruning of spring-blooming shrubs such as lilac and forsythia will reduce flowers for next year. We normally recommend that spring-bloomers be pruned after flowering.
 
Shrubs differ in how severely they can be cutback. Junipers do not break bud from within the plant and therefore should be trimmed lightly if you wish to keep the full shape. Overgrown junipers should be removed. On the other hand, there are certain shrubs that can be pruned back severely during the spring. Rejuvenation is the most severe type of pruning and may be used on multi-stem shrubs that have become too large with too many old branches to justify saving the younger canes. All stems are cut back to 3- to 5-inch stubs. This works well for spirea, forsythia, pyracantha, ninebark, Russian almond, little leaf mock orange, shrub roses, and flowering quince. Just remember that spring is the correct time to do this, not now. (Ward Upham)

Is it a Maple or an Oak?

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​Sometimes people are unsure on how to tell the difference between a maple and an oak. The easiest way is to look at how the leaves are arranged on the stem. Maples are opposite leaved and oaks are alternate. Opposite leaved plants such as maples and ash have leaves directly across from one another. Alternate leaved plants have leaves alternating up the stem; one on one side and the next, further up the stem, on the other. (Ward Upham)

Miscellaneous:
Work Garden Soil in the Fall

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​Fall is the preferred time to prepare garden soil for next spring’s vegetable garden. Spring is often wet making it difficult to work soil without forming clods that remain the rest of the season. Fall usually is drier allowing more time to work the soil when it is at the correct soil moisture content. Even if you work soil wet in the fall and form clods, the freezing and thawing that takes place in the winter will break them down, leaving a mellow soil the following spring.
           
Insects often hide in garden debris. If that debris is worked into the soil, insects will be less likely to survive the winter. Diseases are also less likely to overwinter if old plants are worked under. Also, the garden debris will increase the organic matter content of the soil. Working the debris into the soil is often easier if you mow the old vegetable plants several times to reduce the size of the debris.
           
Fall is an excellent time to add organic matter. Not only are organic materials usually more available in the fall (leaves, rotten hay or silage, grass clippings) but fresher materials can be added in the fall than in the spring because there is more time for them to break down before planting. As a general rule, add 2 inches of organic material to the surface of the soil and till it in. Be careful not to overtill. You should end up with particles like grape nuts or larger. If you work your garden into the consistency of dust, you have destroyed the soil structure. (Ward Upham)

Fall is a Good Time for Soil Testing

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​Though we often think of soil testing as a spring chore, fall can actually be a better time. Soil-testing laboratories are often very busy during the spring resulting in a longer turnaround from submission to recommendations. Also, soils in the spring are often waterlogged, making taking samples difficult. If your soil test suggests more organic matter, fall is a much better season because materials are more available than in the spring, and fresher materials can be used without harming young tender spring-planted plants.
 
Begin by taking a representative sample from several locations in the garden or lawn. Each sample should contain soil from the surface to about 6 to 8 inches deep. This is most easily done with a soil sampler. Many K-State Research and Extension offices have such samplers available for checkout. If you don’t have a sampler, use a shovel to dig straight down into the soil. Then shave a small layer off the back of the hole for your sample. Mix the samples together in a clean plastic container and select about 1 to 1.5 cups of soil. This can be placed in a plastic container such as a resealable plastic bag.
 
Take the soil to your county extension office to have tests done for a small charge at the K-State soil-testing laboratory. A soil test determines fertility problems, not other conditions that may exist such as poor drainage, poor soil structure, soil borne diseases or insects, chemical contaminants or damage, or shade with root competition from other plants. All of these conditions may reduce plant performance but cannot be evaluated by a soil test. (Ward Upham)

Amending Soils with Sand

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Sand is sometimes suggested as an amendment material for clay soils. However, there is good reason to be cautious about using sand. In order for sand to be effective in breaking up a clay soil, sand grains must touch one another so there are pore spaces between grains that can hold air and/or water. If the grains do not touch, the clay fills in all the voids between the sand particles leaving no room for pores.
 
This is the same principle used to make concrete and the result is somewhat the same. You end up making a bad situation worse. So how much sand does it take for it to be effective? Normally, we consider about 80 percent sand to be sufficient. In most cases this makes the use of sand impractical. The addition of organic matter is a much better choice. (Ward Upham)
 
Contributors: Ward Upham, Extension Associate

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Horticulture Newsletter 2016, No. 38

9/20/2016

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Video of the Week:
Protecting Fruit Trees from Deer

Flowers:
Time to Plant Spring-flowering Bulbs

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Late September through October is an excellent time to plant spring-flowering bulbs such as crocus, tulips, and daffodils. These plants need to develop roots in the fall and must meet a chilling requirement over the winter in order to bloom in the spring.
 
Choose a planting site that has full sun to partial shade. The ideal soil would be a sandy loam, but even poor soils can be used if organic material such as peat moss, compost, or aged bark is mixed in. For example, a heavy clay can be amended by mixing in one-third to one-half organic material. Soil pH should be between 6.0 and 7.0.
 
Bulbs need good aeration as well as good drainage for proper development. It is best if the bulbs are given 12 inches of prepared soil. If one-third organic material were added, this would require mixing 4 inches of organic material with 8 inches of soil. Incorporate about 3 pounds of a complete fertilizer such as a 5-10-5 per 100 square feet during preparation or fertilize according to soil test.
 
Planting depths vary depending on the size of the bulbs. For example, tulips and hyacinths are set about 6 inches deep, and daffodils are put 6 to 8 inches deep. Smaller bulbs are planted shallower. As a rule of thumb, bulbs are planted two to three times as deep as their width. Planting depth is the distance from the bottom of the bulb to the top of the soil. Large bulbs are normally spaced 4 to 6 inches apart, and small bulbs about 1 to 2 inches. Planting in clumps or irregular masses produces a better display than planting singly.
 
After placing the bulbs at the proper depth, replace half the soil and add water. This will settle the soil around the bulbs and provide good bulb/soil contact. Add the remaining soil and water again. Although there will be no top growth in the fall, the roots are developing, so soil needs to be kept moist but not soggy. Mulch can be added after the soil has frozen to prevent small bulbs from being heaved out of the soil by alternate freezing and thawing. (Ward Upham)

Vegetables:
Rotation of Vegetable Crops

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Rotating vegetable crops is a standard way of helping prevent disease from being carried over from one year to the next. Rotation means that crops are moved to different areas of the garden each year. Planting the same crop, or a related crop, in the same area each year can lead to a build-up of disease. Also, different crops vary in the depth and density of the root system as well as extract different levels of nutrients. As a rule, cool-season crops such as cabbage, peas, lettuce and onions have relatively sparse, shallow root systems and warm-season crops such as tomatoes, peppers and melons have deeper, better developed root systems. Therefore, it can be helpful to rotate warm-season and cool-season crops.
 
As mentioned earlier, it is also a good idea to avoid planting closely related crops in the same area as diseases may be shared among them. For example, tomatoes, potatoes, peppers and eggplant are closely related. Also, broccoli, cauliflower, cabbage and brussels sprouts share many characteristics in common. Therefore, do not plant cabbage where broccoli was the previous year or tomatoes where the peppers were.
 
So, why is this important to bring this up in the fall?  Now is the time to make a sketch of your garden so that the layout is not forgotten when it is time to plant next year. (Ward Upham)

Ornamentals:
Planting Trees in the Fall

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The fall season can be an excellent time to plant trees. During the spring, soils are cold and may be so wet that low oxygen levels inhibit root growth. The warm and moist soils associated with fall encourage root growth. Fall root growth means the tree becomes established well before a spring-planted tree and is better able to withstand summer stresses. However, certain trees do not produce significant root growth during the fall and are better planted in the spring. These include beech, birch, redbud, magnolia, tulip poplar, willow oak, scarlet oak, black oak, willows, and dogwood.
 
Fall-planted trees require some special care. Remember, that roots are actively growing even though the top is dormant. Make sure the soil stays moist but not soggy. This may require watering not only in the fall but also during the winter months if we experience warm spells that dry the soil. Mulch also is helpful because it minimizes moisture loss and slows the cooling of the soil so root growth continues as long as possible. Evergreens should be moved earlier in the fall than deciduous plants. They need at least six weeks before the ground freezes for the roots to become established. (Ward Upham)

Miscellaneous:
Adding Organic Materials Directly to the Garden

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If the summer weather has brought an early end to your garden, consider adding organic materials directly to the soil rather than composting. Materials such as residue from lawn renovation, rotted hay, or rotted silage can be added and then tilled in. Coarser materials such as tree leaves or garden residue should be shredded. A lawn mower with a bagging attachment can be used to shred this material and collect it in one operation.
 
Organic materials can be spread to a depth of about 3 inches and tilled in. Be sure the soil is not too wet before tilling. During warm weather, the material will decompose quickly and the process can be repeated every two weeks. Later in the fall, it may take longer. This process can be repeated from now until late November to early December.
 
Remember that organic matter helps almost any soil. It improves clay soil by improving tilth, aeration and how quickly the soil takes up water. In sandy soils, it acts as a sponge by holding water and nutrients. (Ward Upham)

Moving Houseplants Inside for the Winter

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Many people with houseplants move some of them outside for the summer to give them better growing conditions and help them recover from the stress of an indoor environment. But as fall approaches and night temperatures approach 50 F, it is time to think about bringing plants inside for the winter. Plants that have spent the summer outside should be inspected for insects and disease before bringing them inside. A sharp spray from a garden hose can remove insects or mites from houseplant foliage. Insects in the potting soil can be forced out by soaking the pot in a tub of lukewarm water for about 15 minutes.
 
Houseplants that have been kept outdoors are accustomed to receiving much more sunlight than they do indoors. So how do we help houseplants acclimatize to the lower light levels inside? Houseplants brought in from outside should be started out in an area of the home that receives plenty of light, and then gradually moved to their permanent, darker location. This process should take four to eight weeks depending on the degree of difference in light levels between the initial and final location of the plant.
 
Understanding plant processes allows us to anticipate potential problems. Acclimatization gives houseplants a greater chance of retaining leaves and avoiding the stress of completely replacing them. (Ward Upham)

Pests:
Itch Mites are Back

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Last year was a bad year for itch mites. It looks like 2016 may be bad as well.  These arthropods are responsible for painful bites that result in itching on people. The mites are barely visible to the naked eye but their bite results in a noticeable raised red area with a centralized blister. It normally takes 10 to 16 hours for itching to start after exposure. Unlike chigger bites which are usually restricted to areas where clothing is tight such as belts, underwear or socks, oak leaf itch mite bites appear where clothing is loose such as at the neck, shoulder and chest.
 
Oak leaf itch mites feed on insect larvae living within straw, seeds and plant galls.  In recent outbreaks, itch mites have been feeding on midge larvae which cause gall formation on the margins of certain oak leaves.  Pin oaks are most likely affected but red oaks and black oaks can also act as a host for the midges. The female mite is able to enter the gall through small openings and paralyze the midge larvae with a neurotoxin.  The midge then acts as a food source for the mite allowing her to develop about 200 offspring. It takes about a week for the new mites to emerge. Only about 5 to 10 percent of the progeny are males. The males do not feed but mate and then die.  Females seek new hosts on the existing tree but can be carried by winds for hundred of yards. Mite populations appear in late July and continue through the summer and into the fall.
 
No effective control has been found. Deet-based repellents have not given consistent results. Tree sprays are ineffective as the mites are protected by the galls.  Oak trees known to be infested with mites should be avoided. If work must be done near oak trees with marginal leaf gall, bathing and changing and washing clothing is recommended. This article was adapted from our publication MF2806, “Oak Leaf Itch Mite.” (Ward Upham)
 
Contributors: Ward Upham, Extension Associate

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Horticulture Newsletter 2016, No. 11

3/15/2016

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Video of the Week:
Pruning Fruit Trees​

Fruit:
Frost Tolerance of Apricots and Peaches

Peach flowers
Growers of apricots and peaches often wonder at what temperature fruit buds are killed especially in years where we have an early spring.  These two tree fruits bloom very early and are often caught by a late frost. The following will give you some guidelines but remember that the actual damage is going to be influenced by the weather before the temperature drops. An extended warm spell before the cold snap may result in more damage due to a loss in cold hardiness. The stages listed are for the fruit buds.
 
Apricot
 
Stage               10% Kill (°F)         90% Kill (°F)
First white             24                              14
First Bloom          25                               19
Full Bloom            27                              22
In the Shuck         27                               24
Green Fruit          28                               25

Peach

Stage              10% Kill (°F)          90% Kill (°F)
Swollen bud          18                                2
Half-inch green   23                                5
Pink                         25                               18
Bloom                     27                               24
Petal fall                28                               25
Fruit set                 28                               25

To check for low temperature injury to fruit buds or blossoms, use a sharp knife and cut them in half longitudinally (from top to bottom). If the tiny seed in the center is white to cream color no damage has been done. But if the seed in several buds or blossoms is dark brown or black, it has been killed.It is possible to give some protection to blossoms from freezing by covering the tree with a bed spread, blanket or similar fabric. Old-fashioned Christmas lights  distributed around the tree will help to give additional protection. The newer, smaller Christmas lights do not give off enough heat and are not recommended. Of course the practicality of this method of protection depends upon the size and number of trees.
 
Sprinkling the tree with water throughout the freezing period can also protect the blossoms. Sprinklers should be started before the temperature drops to freezing to be sure ice does not block the garden hose or water line. Continue until the temperature warms. With this protection method, there is the potential of creating an ice storm. If temperatures remain below freezing for several hours, ice will accumulate on the branches and limbs. The weight from the ice may cause branches and limbs to break causing severe, and possibly permanent, damage to the tree structure. Also, if water drainage from the soil is slow and the water displaces oxygen from the roots, damage to trees may result. (Ward Upham)

Vegetables:
Controlling Weeds in Home Garden Asparagus Beds

asparagus emerging
The best time to control weeds in asparagus is early spring before the asparagus emerges. A light tilling (or hoeing) that is shallow enough to avoid the crowns will eliminate existing weeds. Many gardeners like to mix in organic matter during the same operation.
 
Herbicides can be used before asparagus emerges. Glyphosate (Roundup, Killzall) will kill weeds that are actively growing, and the preemergence herbicide trifluralin can be used to kill weed seeds as they germinate. Trifluralin is found in several products, but not all of them list asparagus on the label. Those that do have asparagus on the label include Miracle-Gro Weed Preventer Granules and Monterey Vegetable and Ornamental Weeder. Mulch can also be used to keep weeds from invading.
 
No herbicides can be used during harvest. The end of harvest presents another opportunity. Remove all fern and spears and apply Roundup to control virtually all of the weeds present.  Past the harvest season and after regrowth of the asparagus, options are limited. Products that contain sethoxydim can be applied to asparagus to kill grassy weeds. Sethoxydim has no effect on broadleaves including asparagus. Two sethoxydim products available to homeowners and
labeled for asparagus are Monterey Grass Getter and Hi-Yield Grass Killer. With broadleaves, the only option is to pull them and look forward to next year. (Ward Upham)

Remove Fern and Fertilize Aspargus

old asparagus ferns
If you haven’t removed last year’s growth from asparagus plants, now is the time. Asparagus comes up around the first of April in Manhattan but will be earlier in southern Kansas and a bit later further north.

Also, asparagus benefits from a fertilizer application early spring. Fertilize according to a soil test or add 1 to 2  pounds of a 10-20-10 fertilizer per 20 feet of row before growth starts. If a soil test shows that only nitrogen is needed, apply 1 pound of a 16-0-0 product or ½ pound of a 30-4-5, 27-3-3 or similar fertilizer per 20 feet of row. Incorporate lightly with a tiller or rake in fertilizer before spears emerge. Fertilize again at the same rate after the last harvest. (Ward Upham)

Flowers:
Preventing Weeds in Flower Beds

flower bed
Often mulch does a good enough job in perennial flower beds to prevent weeds but sometimes the mulch needs a little help. In annual beds, judicious hoeing will keep weeds down until the foliage forms a canopy that prevents weed germination.  However, a lack of time may have you considering an easier way than hoeing or pulling weeds that come through mulch. Preemergence herbicides can help though you should not expect 100% control.
 
Preemergence herbicides do not keep the weed seed from germinating but kill the young plant as it starts to grow. It is necessary to water these products in (1/4 inch of water) so that the young weed root will contact the herbicide. Be aware that most of these products are more effective on grassy weeds such as crabgrass rather than broadleaves such as dandelions or spurge.
 
These herbicides often have no effect on existing plants, so they must be applied before the weed seed germinates. Additionally, preventers do not last forever once applied to the soil. Microorganisms and natural processes begin to gradually break them down soon after they are applied. However, all should last long enough so that you get canopy cover before the herbicide wears off.
 
Read the label for information on when to apply the product. Also, be sure the ornamental plants within the bed area are on the label before purchasing the product. See below for products we can use.
 
Dimension (dithopyr)
- Hi-Yield Turf & Ornamental Weed and Grass Stopper
- Bonide Crabgrass & Weed Preventer

​Treflan (trifluralin)
- Hi-Yield Herbicide Granules Weed and Grass Preventer
- Miracle Gro Garden Weed Preventer
- Preen Weed Preventer
(Ward Upham)

Turfgrass:
Managing Turf in the Shade

shaded turf
Turfgrasses differ in their capacity to grow in shade. Among Kansas turfgrasses, tall fescue is the best adapted to shade though it isn’t all that good. Although the fine fescues (i.e., creeping red, chewings, hard and sheep) have better shade tolerance, they lack heat tolerance and typically decline during hot Kansas summers. The warm-season grasses have the poorest shade tolerance, although zoysia does better than Bermuda or buffalo. Where shade is too heavy for fescue, there are other courses of action. The most obvious is to either remove trees, or to prune limbs and thin the tree canopies. Grass will do better under openly spaced trees than under closely spaced trees. Pruned limbs and thinned canopies will allow more sunlight to directly reach the turfgrass. If possible, raise the mowing height in the shade to compensate for the more upright growth of the leaves, and to provide more leaf area for photosynthesis. The thin, weak turf in the shade may tempt you to fertilize more.
 
Remember the problem is lack of light, not lack of fertility. Too much nitrogen in the spring causes the plant to grow faster and may result in weak plants. The nitrogen rate for shaded grass should be cut back to at least half of that for grass in full sun. Late fall fertilization after tree leaves have fallen, on the other hand, is important for shaded cool-season turfgrasses and should be applied at a full rate. Irrigate infrequently but deeply. Light, frequent irrigation may encourage tree feeder-roots to stay near the surface, which increases competition between the trees and the turf. Restrict traffic in the shade.
 
Many times, the best choice for shaded areas is switch from a turfgrass to a more shade-tolerant plant. For example, English ivy and periwinkle (Vinca minor) are much more shade tolerant than any turfgrass adapted to our area. Another option is simply to mulch the area where turf doesn’t grow well. The trees will love the cool, moist soil and the absence of competition. (Ward Upham)

Ornamentals:
Brown Coloration on Junipers

Juniper male
Certain eastern redcedar and various other junipers are showing a brownish cast when viewed from a distance. This may be the male flowers. Male flowers are on the tips of the leaves and look somewhat like a cross between a miniature hand grenade and a pinecone. Shaking the branches on dry days will often result in a cloud of pollen being released.
 
Most junipers are dioecious, meaning they have both male and female plants. About half the junipers (the males) will have this coloration. The female flowers are much less obvious. If you have clients who are concerned about this brown coloration, have them check the plants to ensure the male flowers are the cause. If they are, assure them that this is normal and will fade with time. (Ward Upham)

Miscellaneous:
Adding Organic Matter in the Spring

adding organic matter
Organic matter is a good way to improve garden soil as it improves a heavy soil by bettering tilth, aeration and how quickly the soil absorbs water. However, organic matter added in the spring should be well decomposed and finely shredded/ground. Manures and compost should have a good earthy smell without a hint of ammonia. Add a 2-inch layer of organic matter to the surface of the soil and work the materials into the soil thoroughly. Be sure soils are dry enough to work before tilling as wet soils will produce clods.
 
To determine if a soil is too wet to work, grab a handful and squeeze. If water comes out, it is much too wet. Even if no water drips out, it still may not be dry enough to work. Push a finger into the soil you squeezed. If it crumbles, it is dry enough, but if your finger just leaves an indentation, more time is needed. Be sure to take your handfuls of soil from the depth you plan to work the soil because deeper soils may contain more moisture than the surface. (Ward Upham)
 
Contributors:  Ward Upham, Extension Associate

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Horticulture Newsletter 2016, No. 8

2/23/2016

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Video of the Week:
Soil Testing: Using Test Strips

Fruit:
Growing Blueberries

planting blueberries
Blueberries are not native to Kansas but will grow in the eastern half of the state with good preparation. They are related to azaleas and rhododendrons and require an acid pH, preferably 4.8 to 5.2. Blueberries do not have root hairs, so watering and mulching are important.
 
It is best to start planting preparations a year ahead of time to allow for pH adjustment, weed control, and the addition of organic matter. The first step is a soil test to determine how much the pH needs to be reduced. For a pH up to 5.5, the addition of sphagnum peat moss at the rate of 2 cubic feet per 100 square feet will be adequate. For a pH 5.5 to 6.0, add 1 pound of sulfur per 100 square feet of bed in addition to the peat moss. For a pH 6.0 to 6.5, add 1.5 pounds of sulfur per 100 square feet of bed. For pH levels above 6.5, use 2 pounds of sulfur per 100 square feet of bed and double the amount of sphagnum peat moss suggested earlier. Do not use aluminum sulfate to correct a high pH because excessive levels of aluminum can be toxic to blueberries. For each 0.5 movement up the pH scale from 6.5, add an additional pound of sulfur. Sulfur can be applied as a dust, but pelletized sulfur is much easier to spread.
 
Treat only the row. Row width should be 8 feet. Blueberries are normally spaced about 5 feet within the row. Sulfur takes time to react, so allow as much time as possible between sulfur application and planting. Blueberries will bear more if you plant more than one variety.
 
Recommended varieties vary, but you may want to try Bluecrop because it is adaptable. Patriot also seems to do well. You may want to try some other varieties.
 
Blueberries should be mulched. Sawdust is the traditional material, but straw and wood chips will work as well. Mulch to a depth of about 3 inches.
 
Blueberries must be irrigated. Soils should be kept most but never waterlogged. Adding peat moss to the planting row will elevate the planting bed enough that standing water should not be an issue. An elevated bed will dry out more quickly, so there must be a means of adding water. Trickle irrigation works well. Watering twice a week during the summer with enough water to wet the soil 8 inches deep should be sufficient except under extreme heat. Watering once a week may be enough during the cooler spring and fall weather. As you might guess, there is more to growing blueberries than can be included in a short article. Dr. Art Gaus from the University of Missouri shared this instruction sheet on how to grow blueberries more than 25 years ago. It is still excellent information on blueberry culture. You can access it by going to: http://www.hfrr.ksu.edu/doc3091.ashx
 
Blueberries require commitment. Anything less than excellent preparation and care will result in failure. (Ward Upham)

Blueberries in Containers

blueberries
Growing blueberries in containers is becoming more popular. Chosen varieties are usually half-high plants that are a cross between highbush and lowbush blueberry species. Plants can be as small as 18 inches tall and wide (Top Hat), but typically are larger. Here are several tips for producing container grown blueberries:
 
Acid soil pH: Blueberries need an acid pH between 4.8 and 5.2. Sphagnum peat moss is very acid and often used in large quantities in soil mixes for acid-loving plants. In fact, blueberries can be grown in peat moss alone if nutrients are provided but that is an involved process. A 50/50 mix of peat moss and potting soil is recommended. This will provide nutrients and weight so the plant is less likely to blow over in wind.
 
Container size: Though containers as small as 2 gallons can be used for half-high blueberries, a larger container will be more stable in the wind and provide a larger moisture reserve during hot, dry weather.
 
Watering: Blueberries do not have root hairs, so they are not efficient in picking up water. Potting soil should be kept moist. This will likely be the most challenging aspect of growing blueberries in containers. A large container will not need to be watered as frequently as a small one.
 
Winter care: Though plants are winter hardy, the roots are not. Move pots into an unheated, attached garage or bury them in the soil or mulch enough to bury the pot in early November. Water them periodically during the winter. Use your finger to determine if the soil is moist one inch deep. If not, then water until some flows out the bottom of the pot.
 
Varieties: Though blueberries will produce some fruit if only a single variety is grown, two varieties will increase the potential fruit crop. Suggested varieties include Top Hat and Northsky. Each should reach about 18 inches high, though Northsky will likely grow wider than Top Hat.

Northblue is another choice that should produce more fruit than either Top Hat or Northsky but should reach 2 to 3 feet high. North Country is intermediate in size at 18 to 24 inches high and should produce a moderate amount of fruit.
 
Wind protection: Wind protection will decrease the amount of water these plants need and reduce the chances of leaf scorch. 

Exposure: Blueberries do best with a minimum of 6 to 8 hours of sunlight a day. Try a northern or eastern exposure. (Ward Upham)

Lettuce

lettuce
Though lettuce is most often planted directly from seed in late March to early April, it can be started from transplants. Transplants allow lettuce to mature earlier so that it escapes the excessive heat that can lead to a strong flavor and bitterness.
 
Seed should be started four to five weeks before transplanting. Because transplants are placed at the same time as direct seeding, now would be a good time to begin. Use a seed starting mix and plant shallow as lettuce requires light for
germination. A soil media temperature of 60 to 68 degrees will encourage germination. Watch the media temperature carefully, as seed can enter a thermal dormancy if germination temperatures are excessive. Also, a cooler temperature of 55 to 60 degrees should be used once the plants emerge.
 
Time to maturity varies depending on the type of lettuce, with leaf lettuce being the quickest, followed by bibb, romaine, and buttercrunch lettuce. Head or crisphead lettuce is the slowest and is least likely to mature before becoming bitter.
 
Spacing also varies with type. Leaf lettuce plants are spaced 4 to 6 inches apart, buttercrunch, bibb, and romaine are set at 6 to 8 inches and head lettuce should be at least 8 inches apart in the row. Lettuce does not have an extensive root system and requires regular watering if rainfall is lacking.
 
Fertilize before planting according to soil test. Plants should also be sidedressed when about 1/3 grown. Sidedressing is done with fertilizers that have more nitrogen than phosphorus and potassium. Use 1/3 cup of nitrate of soda (16-0-0) or 1/4 cup of a 27-3-3, 29-5-4 or similar fertilizer per 10 feet of row. The latter fertilizers are lawn fertilizers but will work well for sidedressing as long as they do not contain weed killers or weed preventers. (Ward Upham)

Turfgrass:
Lawn Calendar for Warm-Season Grass

warm-season grass lawn
Following is a lawn calendar for Zoysia-grass and Bermudagrass. Buffalograss, also a warm-season grass, is covered in a separate article.
 
March
Spot treat broadleaf weeds if necessary. Treat on a day that is 50 degrees F or warmer. Rain or irrigation within 24 hours of application will reduce effectiveness.
 
April
Apply crabgrass preventer between April 1 and April 15, or apply preventer when the eastern redbud is in full bloom. If using a product with prodiamine (Barricade), apply two weeks earlier. Crabgrass preventers must be watered in before they will start to work.
 
May – August 15
Fertilize with 1 lb. of nitrogen per 1,000 square feet per application. Follow the recommendations on the bag. More applications will give a deeper green color, but will increase mowing and lead to thatch buildup with zoysiagrass. Bermudagrass can also have problems with thatch buildup but thatch is less likely with Bermuda than zoysia.

Bermudagrass – Use two to four applications.
Zoysiagrass – Use one to two applications. Too much nitrogen leads to thatch buildup.
 
One Application: Apply in June.
Two Applications: Apply May and July.
Three Applications: Apply May, June, and early August.
Four Applications: Apply May, June, July, and early August.
 
June
If grubs have been a problem in the past, apply a product containing imidacloprid by mid July. Imidacloprid can be applied as early as mid May if there are problems with billbugs or May beetle grubs. These products kill the grubs before they cause damage. They are effective and safe but must be watered in before they become active. June is a good time to core aerate a warm-season lawn. Core aeration will help alleviate compaction, increase the rate of water infiltration, improve soil air exchange and help control thatch.
 
Late-July through August
If you see grub damage, apply a grub killer. If Imidacloprid has been applied, this should not be necessary. Grub killers must be watered in immediately.
 
Late October
Spray for broadleaf weeds if they are a problem. Treat on a day that is at least 50 degrees F. Rain or irrigation within 24 hours reduces effectiveness.  Use the rates listed on the label for all products mentioned. (Ward Upham)

Lawn Calendar for Buffalograss

Buffalograss lawn
General Comments
Buffalograss has become more popular in recent years due to its reputation as a low-maintenance grass. Buffalograss does require less water and fertilizer than our other turfgrasses but often has problems competing with weeds in eastern Kansas.

Buffalograss is an open growing grass that will not shade the soil as well as most of our other turfgrasses. Weeds are often the result. A regular mowing schedule can reduce broadleaf weed problems as most broadleaves cannot survive consistent mowing. Those that do either have a rosette growing pattern (dandelions, shepherds purse) or are “creepers” (henbit, chickweed, spurge). Annual grasses such as crabgrass or foxtail can also be a problem. A good weed preventer (prodiamine, pendimethalin or dithiopyr) may be needed prevent problems.
 
March
Spot treat broadleaf weeds if necessary. The most important treatment for broadleaf weeds should be in late October to early November well after the buffalograss is dormant. Treatments are much more effective then than in the spring as the weeds are smaller and the weeds are sending energy, as well as the herbicide, to the roots. Treatments in March are to take care of any “escapes” missed in the fall spraying. Spray early enough in March that the buffalograss is still dormant. Look at the base of the plants to make sure there is no green. Treat on a day that is 50 degrees F or warmer. Rain or irrigation within 24 hours of application will reduce effectiveness. Use a combination product such as Trimec, Weed-B-Gon or Weed-Out. Weed Free Zone is also good and will give quicker results under cool conditions.
 
April
Apply crabgrass preventer between April 1 and April 15, or apply preventer when the eastern redbud is in full bloom. If using a product with prodiamine (Barricade), apply two weeks earlier. Crabgrass preventers must be watered in before they will work. Avoid using broadleaf herbicides as the buffalograss is greening up as injury can result. The buffalograss will not be killed but growth will slow making the buffalograss less competitive with weeds.
 
June
Fertilize with 1 lb. of nitrogen per 1,000 square feet during June. More applications will give a deeper green color, but will encourage weeds. If it is felt that a second application is needed, apply in July.  If grubs have been a problem in the past, apply a product containing imidacloprid by mid July.
 
Imidacloprid can be applied as early as mid May if there are problems with billbugs or May beetle grubs. These products kill the grubs before they cause damage. They are effective and safe but must be watered in before they become active. Again, I would only treat if grubs have been a problem in the past. Note that the whole area may not need to be treated. The beetles that lay the eggs for the grubs are attracted to lights and moist soil and those areas are most likely to be infested.
 
Late-July through August
If you see grub damage, apply a grub killer. If imidacloprid has been applied or if grubs have not been a problem in the past, this should not be necessary. Grub killers must be watered in immediately.
 
Late October to Early November
Spray for broadleaf weeds if they are a problem. Look carefully as our winter annuals such as chickweed and henbit are small and easily overlooked. Use a product that contains 2,4-D as it increases effectiveness on dandelions. Treat on a day that is at least 50 degrees F. Rain or irrigation within 24 hours reduces effectiveness.  Use the rates listed on the label for all products mentioned. (Ward Upham)

Flowers:
Iris Leaf Spot Control Begins Now

Iris leaf spot
Now is a good time to begin control measures for iris leaf spot by removing old, dead leaves. Iris leaf spot is a fungus disease that attacks the leaves and occasionally the flower stalks and buds of iris. Infection is favored by wet periods during the spring, and emerging leaves eventually show small (1/8- to 1/4-inch diameter) spots. The borders of these spots are reddish, and surrounding tissue first appears water-soaked, and then yellows. Spots enlarge  after flowering and may coalesce. The disease tends to be worse in wet weather and may kill individual leaves. Though the disease will not kill the plant directly, repeated attacks can reduce plant vigor so that the iris may die from other stresses. Spores are passed to nearby plants by wind or splashing water.
 
Because this disease overwinters in old leaves, removal and destruction of dead leaves will help with control. For plants that had little infection the previous year, this may be all that is needed. Plants that were heavily infected last year should be sprayed with chlorothalonil (Bravado Fungicide, Fertilome Broad Spectrum Landscape & Garden Fungicide, Ortho Garden Disease Control, GardenTech Daconil, Bonide Fungonil, Bravo Flowable Fungicide) or myclobutanil (Immunox, Immunox Plus) starting when leaves appear in the spring. Repeat sprays every seven to 10 days for four to six sprays. Iris leaves are waxy, so be sure to include a spreader-sticker in your spray to ensure good coverage. (Ward Upham)
 
Contributors:  Ward Upham, Extension Associate

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    Authors

    Ward Upham runs the Horticulture Response Center in the Department of Horticulture and Natural Resources at Kansas State University. Other contributors include K-State Extension Specialists.

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