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2014 Horticulture Newsletter, No. 34

8/26/2014

Video of the Week:
Overseeding your Lawn

Turfgrass:
Give Cool-Season Grasses a Boost

September is almost here and that means it is prime time to fertilize your tall fescue or Kentucky bluegrass lawns. If you could only fertilize your cool-season grasses once per year, this would be the best time to do it.

These grasses are entering their fall growth cycle as days shorten and temperatures moderate (especially at night). Cool-season grasses naturally thicken up in the fall by tillering (forming new shoots at the base of existing plants) and, for bluegrass, spreading by underground stems called rhizomes. Consequently, September is the most important time to fertilize these grasses.

Apply 1 to 1.5 pounds of actual nitrogen per 1,000 square feet. The settings recommended on lawn fertilizer bags usually result in about 1 pound of nitrogen per 1,000 square feet. We recommend a quick-release source of nitrogen at this time. Most fertilizers sold in garden centers and department stores contain either quick-release nitrogen or a mixture of quick- and slow-release. Usually only lawn fertilizers recommended for summer use contain slow-release nitrogen. Any of the others should be quick-release.

The second most important fertilization of cool-season grasses also occurs during the fall. A November fertilizer application will help the grass green up earlier next spring and provide the nutrients needed until summer. It also should be quick-release applied at the rate of 1-pound actual nitrogen per 1,000 square feet. (Ward Upham)

Power Raking and Core-Aeration

September is the optimum time to power rake or core-aerate tall fescue and Kentucky bluegrass lawns. These grasses should be coming out of their summer doldrums and beginning to grow more vigorously. This is a good time to consider what we are trying to accomplish with these practices.

Power raking is primarily a thatch control operation. It can be excessively damaging to the turf if not done carefully. For lawns with one-half inch of thatch or less, I don’t recommend power raking but rather core aeration. For those who are unsure what thatch is, it is a springy layer of light-brown organic matter that resembles peat moss and is located above the soil but below the grass foliage. Power raking pulls up an incredible amount of material that then must be dealt with by composting or discarding.

Core-aeration is a much better practice for most lawns. By removing cores of soil, core-aeration relieves compaction, hastens thatch decomposition, and improves water, nutrient, and oxygen movement into the soil profile. This operation should be performed when the soil is just moist enough so that it crumbles easily when worked between the fingers. Enough passes should be made so that the holes are spaced about 2 to 3 inches apart. Ideally, the holes should penetrate 2.5 to 3 inches deep. The cores can be left on the lawn to decompose naturally (a process that usually takes two or three weeks, depending on soil-type), or they can be broken up with a vertical mower set just low enough to nick the cores, and then dragged with a section of chain-link fence or a steel doormat. The intermingling of soil and thatch is beneficial to the lawn. (Ward Upham)

Flowers:
Peonies May be Cut Back Now

Peonies often look a little bedraggled by this time of year and gardeners may want to cut them back. That will not be a problem with this perennial. Peonies are essentially dormant by September 1 even though leaves may still be green. Cut leaves off close to the ground and compost or discard. (Ward Upham)

Ornamentals:
Big XII Gardening

Ready to gear up for football season, K-State fans? What better way to cheer on the Wildcats than by featuring plants with purple accents in your landscape. As you know, there are several categories of plants from which to choose including annual bedding/container plants, perennials, bulbs and woody shrubs or trees. Depending on your level of commitment to K-State-themed gardening, there are multiple ways to celebrate our beloved sports teams.

For instant color, consider a container combination with any purple (angelonia, petunia, etc.), white (petunia or vinca) or gray (lambs ears) plants. Make sure they can all be grown in the same sun and water conditions. Check out www.prairiestarflowers.com for more ideas and cultivar recommendations. Go shopping at your local garden center and see what you can find!

For those of you who like to plan ahead, there are many woody plants that may take a few years to mature in your landscape, but are well worth the investment. Most feature purple blooms or purple leaves (specimen plants!). Download the new “Deciduous Shrubs for Kansas” publication (http://www.ksre.ksu.edu/bookstore/pubs/MF3116.pdf), open it on your computer and run a search for “purple” in the document. This should give you plenty of options.

One of the gardeners in my neighborhood celebrates Big XII football every year by painting a small wooden slate in the colors of the teams we will play. He places the blank slates on his fence and, after each game, he paints the score on the no-longer-blank slate. It’s a great visual reminder of something that is important to him and of interest to lots of folks driving by. It also makes interesting and relevant garden art.

How about container gardening in the colors of the Big XII? If you think about it, throughout the 10 teams in the conference, the same colors are used in combination: red, orange, yellow, green, blue, violet, white, gray and black. You could grow containers that each feature a plant with one of these colors, then move them around in different combinations depending on which teams are playing at any given time. Sound like fun?

I had one more thought on Big XII gardening: plant a small arrangement along a fence or in a planting bed for each team in the conference, featuring their colors. Maybe with a scoreboard above it? Well… I suppose it wouldn’t be a particularly great reminder if those flowers were still living long after the results of the game were available. Hmm… Roundup® the plants when we beat them? Ha! JUST KIDDING! (Cheryl Boyer)

Are Crabapples Safe to Eat?

Crabapples are safe to consume as long as you don’t eat too many of them. Actually, the only difference between crabapples and apples is the size of the fruit. By definition, crabapples have fruit that are 2 inches or less in diameter, and apples are more than 2 inches in diameter. By this definition, most of the apples grown from seed will be crabapples. The fruiting apples are grafted. So did people ever plant crabapples from seed? Of course they did. Just think of Johnny Appleseed. But those apples were normally used for jelly, applesauce, and cider and not for fresh eating.

There is one other caveat with using crabapples from a tree in the landscape. Make sure the tree hasn't been sprayed as an ornamental with a pesticide that isn't labeled for fruit tree apples. If it has, then the fruit should not be used. (Ward Upham)

Pests:
Yellowjacket Season is Here

In the past two weeks an increasing number of calls have been received regarding honey bees, or aggressive honey bees at various K-State offices. Follow-up on these calls have revealed that these are not honey bees, but yellow jackets. Yellow jackets tend to begin most of their noticeable scavenging beginning around mid-August continuing until the fall weather turns cold.

Yellow jacket wasps are ¾” in length and can resemble honey bees from a distance, but have a few distinctions. Yellow jackets are more likely to be around human food, pet food, and compost piles. They tend to nest in the ground, but can also be found in house cavities, tree cavities, or in compost piles which have not been disturbed. Honey bees have more hairs and are usually duller in color.

If you encounter a yellow jacket nest, it is best to leave the area. Yellow jackets are more likely to sting when a nest is near. They will also sting when trying to be swatted at or if accidentally encountered when drinking soda from a can they’ve crawled into.

To prevent encounters, remove attractive sources of food. Keep pet food covered or indoors, especially when not in use. Seal garbage cans and empty regularly. Pick up and dispose of ripe fruit. If you must move something in the area of a nest, it is recommended to do this before dawn or after dusk when yellow jackets are less active. (Sharon Dobesh)

Contributors: Cheryl Boyer, Extension Nursery Crops Specialist; Sharon Dobesh, Associate Director, Plant Pathology; Ward Upham, Extension Associate

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Horticulture Newsletter 2014, No. 33

8/19/2014

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Video of the Week:
Grow Your Own Salad Mix

Turfgrass:
Overseeding a Lawn

Tall fescue lawns that have become thin over the summer can be thickened up by overseeding during September. Start by mowing the grass short (1 to 1.5 inches) and removing the clippings. This will make it easier to achieve good seed-soil contact and increase the amount of light that will reach the young seedlings.

Good seed-soil contact is vital if the overseeding is to be successful. Excess thatch can prevent seed from reaching the soil and germinating. Normally we want 1/4 inch of thatch or less when overseeding. If the thatch layer is 3/4 inch or more, it is usually easiest to use a sod cutter to remove it and start over with a new lawn. A power rake can be used to reduce a thatch layer that is less than 3/4 inch but more than a quarter inch.

Once thatch is under control, the soil should be prepared for the seed. This can be done in various ways. A verticut machine has solid vertical blades that can be set to cut furrows in the soil. It is best to go two different directions with the machine. A slit seeder is a verticut machine with a seed hopper added so the soil prep and seeding operation are combined. A third option is to use a core aerator.

The core aerator will punch holes in the soil and deposit the soil cores on the surface of the ground. Each hole produces an excellent environment for seed germination and growth. Make three to four passes with the core aerator to insure enough holes for the seed. Using a core aerator has the additional benefit of reducing the amount of watering needed to get the seed germinated and growing. Aeration also increases the water infiltration rate, decreases compaction, and increases the amount of oxygen in the soil. Fertilizer should then be applied at the rate suggested by a soil test, or a starter fertilizer should be used at the rate suggested on the bag. (Ward Upham)

Fall Lawn Seeding Tips

The keys to successful lawn seeding are proper rates, even dispersal, good seed to soil contact, and proper watering. Evenness is best achieved by carefully calibrating the seeder or by adjusting the seeder to a low setting and making several passes to ensure even distribution. Seeding a little on the heavy side with close overlapping is better than missing areas altogether, especially for the bunch-type tall fescue, which does not spread. Multiple seeder passes in opposite directions should help avoid this problem.

A more serious error in seeding is using the improper rate. For tall fescue, aim for 6 to 8 pounds of seed per 1,000 square feet for new areas and about half as much for overseeding or seeding areas in the shade. Using too much seed results in a lawn more prone to disease and damage from stress. The best way to avoid such a mistake is to determine the square footage of the yard first, and then calculate the amount of seed. Using too little seed can also be detrimental and result in clumpy turf that is not as visually pleasing.

Establishing good seed to soil contact is essential for good germination rates. Slit seeders achieve good contact at the time of seeding by dropping seed directly behind the blade that slices a furrow into the soil. Packing wheels then follow to close the furrow. The same result can be accomplished by using a verticut before broadcasting the seed, and then verticutting a second time.

Core aerators can also be used to seed grass. Go over an area at least three times in different directions, and then broadcast the seed. Germination will occur in the aeration holes. Because those holes stay moister than a traditional seedbed, this method requires less watering. If seeding worked soil, use light hand raking to mix the seed into the soil. A leaf rake often works better than a garden rake because it mixes seed more shallowly.

Water newly planted areas lightly, but often. Keep soil constantly moist but not waterlogged. During hot days, a new lawn may need to be watered three times a day. If watered less, germination will be slowed. Cool, calm days may require watering only every couple of days. As the grass plants come up, gradually decrease watering to once a week if there is no rain. Let the plants tell you when to water. If you can push the blades down and they don't spring back up quickly, the lawn needs water. Once seed sprouts, try to minimize how much traffic (foot, mower, dog, etc.) seeded areas receive until the seedlings are a little more robust and ready to be mowed. Begin mowing once seedlings reach 3 to 4 inches tall. (Ward Upham)

Flowers:
Dividing Daylilies

Daylilies need to be divided every three to four years to maintain vigor. Though they may be divided in early spring before growth starts, it is more common to divide them at this time of year. Many gardeners cut back the tops to about half their original height to make plants easier to handle.

Daylilies have a very tough root system that can make them difficult to divide while in place. Dividing in place is practical if it hasn’t been long since the last division. In such cases, a spading fork can be used to peel fans from the existing clump. If the plants have been in place longer and are well grown together, it is more practical to divide them after the entire clump has been dug.

Use a spade to lift the entire clump out of the ground. Although it is possible to cut the clump apart with a sharp spade, you'll save more roots by using two spading forks back-to-back to divide the clump into sections. Each section should be about the size of a head of cauliflower. An easier method involves using a stream of water from a garden hose to wash the soil from the clump, and then rolling the clump back and forth until the individual divisions separate.

Space divisions 24 to 30 inches apart, and set each at its original depth. The number of flowers will be reduced the first year after division but will return to normal until the plants need to be divided again. (Ward Upham)

Fruit:
Pear Harvest

Pears should not be allowed to ripen on the tree. They should be picked while still firm and ripened after harvest. Tree-ripened fruits are often of poor quality because of the development of grit cells and the browning and softening of the inner flesh. Commercial growers determine the best time to harvest pears by measuring the decrease in fruit firmness as the fruit matures. This varies with growing conditions and variety. A Magness meter is used for testing and measures the pressure needed to push a 5/16-inch tip a specified distance into an individual fruit. Home gardeners can use these other indicators:

1. A change in the fruit ground color from a dark green to light green or yellowish green. The ground color is the "background" color of the fruit.

2. Fruit should part easily from the branch when it is lifted up and twisted.

3. Corking over of lenticels. Lenticels are the "breathing pores" of the fruit. They start out as a white to greenish white color and turn brown due to corking as the fruit nears maturity. They look like brown “specks” on the fruit.

4. Development of characteristic pear aroma and taste of sampled fruit.

Pears ripen in one to three weeks after harvest if held at 60 to 65 degrees F. They can then be canned or preserved. If you wish to store some for ripening later, fresh-picked fruit should be placed in cold storage at 29 to 31degrees F and 90 percent humidity. Ripen small amounts as needed by moving them to a warmer location and holding them at 60 to 65 degrees F. Storing at too high a temperature (75 degrees F and higher) will result in the fruit breaking down without
ripening. (Ward Upham)

Vegetables:
Harvesting Winter Squash

Summer squash such as zucchini and scallop are harvested while immature but winter squash such as acorn, hubbard and butternut are harvested later, in the mature stage, after the rind is tough and seeds have developed. We normally think September is the time that winter squash are harvested. Harvesting too early leads to fruit that shrivels and rots.

There are two main characteristics that help tell us when winter squash are mature: color and rind toughness.

Winter squash change color as they become mature. Butternut changes from light beige to deep tan. Acorn is a deep green color but has a ground spot that changes from yellow to orange when ripe. Gray or orange is the mature color for hubbard.

Hard, tough rinds is another characteristic of mature winter squash. This is easily checked by trying to puncture the rind with your thumbnail or fingernail. If it easily penetrates the skin, the squash is not yet mature and will lose water through the skin -- causing the fruit to dry and shrivel. Also, immature fruit will be of low quality. The stem should also be dry enough that excessive water doesn’t drip from the stem.

Winter squash should be stored cool with elevated humidity. Ideal conditions would be 55 to 60 degrees F and 50 to 70 percent relative humidity. Under such conditions, acorn squash will usually last about 5 to 8 weeks, butternuts 2 to 3 months and hubbards 5 to 6 months. (Ward Upham)

Common Smut on Sweet Corn

Smut (Ustilago maydis) is a fungal disease of corn that may infect leaves, stems, tassels or ears though infections on ears are the most obvious. Immature galls are white and spongy but become brown with dark powdery spores with maturity. Leaf galls remain small but those on the ears or stems can become rather large and will release large numbers of spores when they rupture. This disease is likely to be most severe on plants injured by hail, cultivation or insects and tends to be worse on soils that have had heavy applications of nitrogen fertilizer or manure. Also anything that slows growth such as hot, dry weather or cool, wet weather when the plants are young can result in more infections.

Immature smut galls are considered an edible delicacy known as cuitlacoche in Mexico. They are a high value crop for some growers in the northeast U.S. who sell them to Mexican restaurants.

There is no chemical control for this disease. Crop rotation and a balanced fertilizer program can help minimize this disease. Remove and destroy galls from infected plants before they rupture. (Ward Upham)

Miscellaneous:
Pokeweed

A number of people have asked the name of the weed with the large leaves and purple-black berries that hang in a cluster. This perennial is known as pokeweed. All parts of this plant are poisonous, especially the roots. Signs of poisoning include abdominal cramps, diarrhea, vomiting, weakness, drowsiness and difficulty in breathing. One of the toxins found in pokeweed is the protein lectin, which can cause abnormalities in white blood cells.

Surprisingly, young leafy springtime shoots are sometimes eaten after thorough cooking. Though cooking eliminates most of the toxins, there is still a danger of being poisoned from handling and preparing the shoots as well as ingesting improperly cooked plants.

Berries can be attractive to children. Cut down and discard pokeweed that might come into contact with kids. This plant is a perennial. You may want to spray it with a herbicide next year before it is large enough to be attractive to children. (Ward Upham)

Contributors: Ward Upham, Extension Associate

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Horticulture Newsletter 2014, No. 32

8/12/2014

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Video of the Week:
When is Watermelon Ripe on the Vine?

Turfgrass:
Recommended Tall Fescue Cultivars

Though several cool-season grasses are grown in Kansas, tall fescue is considered the best adapted and is recommended for home lawns. The cultivar K-31 is the old standby and has been used for years. However, there is a myriad of newer cultivars that have improved color, density and a finer leaf texture. Most of these newer varieties are very close to one another in quality.

Each year we the National Turfgrass Evaluation Trial rates tall fescue varieties for color, greenup, quality and texture. Quality ratings are taken once a month from March through October. K-31 consistently rates at the bottom. The recommended cultivars were 3rd Millennium, Braveheart, Bullseye, Catalyst, Cochise, Corona, Escalade, Faith, Falcon V, Firecracker, Firenza, Jamboree, LS 1200, Monet, Mustang, Raptor II, Rhambler SRP, RK5, Shenandoah III, Shenandoah Elite, Sidewinder, Spyder LS, Talladega, Turbo and Wolfpack II. There are a number of other cultivars that did not make this list but should do well in Kansas. Go to http://ntep.org/data/tf06/tf06_12-10f/tf0612ft04.txt . Any variety with a mean rating of 6.0 or above should be fine. K-31 has a rating of 4.1. Keep in mind that mixes of several varieties may allow you to take advantage of differing strengths. It is not necessary for mixes to contain only the varieties mentioned above.

Though K-31may still be a good choice for large, open areas, the new cultivars will give better performance for those who desire a high-quality turf. (Ward Upham)

Kentucky Bluegrass Variety Selection for Cool-Season Lawns

Though Kentucky bluegrass is not as heat and drought tolerant as tall fescue and the warm-season grasses, it is commonly used in northeastern Kansas, where there is sufficient annual rainfall. It is also grown under irrigation in northwestern Kansas where the higher elevation allows for cooler summer night temperatures.

The following cultivars have performed well compared to other bluegrasses in this region. Use this list as a guide. Omission does not necessarily mean that a cultivar will not perform well. Recommended cultivars for high-quality lawns, where visual appearance is the prime concern, include Alexa II, Aura, Award, Bewitched, Barrister, Belissimo, Beyond, Diva, Everest, Everglade, Excursion, Ginney II, Granite, Impact, Midnight, NuChicago, NuGlade, NuDestiny, Rhapsody, Rhythm, Rugby, Skye, Solar Eclipse, STR 2485, Sudden Impact, Washington and Zifandel. Such lawns should receive 4 to 5 pounds nitrogen per 1,000 square feet per year and would typically be irrigated during dry periods to prevent drought stress.

Cultivars that do relatively well under a low-maintenance program with limited watering often differ from those that do well under higher inputs. Good choices for low maintenance include Baron, Baronie, Caliber, Canterbury, Dragon, Eagleton, Envicta, Kenblue, North Star, and South Dakota. Instead of the 4 to 5 pounds of nitrogen per 1,000 square feet per year, low-maintenance program would include 1 to 2 pounds of nitrogen per 1,000 square feet per year. Obviously, a low-input lawn will not be as attractive as a higher-input lawn, but you can expect the cultivars listed above to look fairly good in the spring and fall, while going dormant in the summer. (Ward Upham)

For Seeding Success, Pay Attention to "Other Crop" on the Seed Label

Fall planting time is close at hand, so it's time to talk about grass seed. Many people have the idea that all grass seed is basically the same. Big mistake! Choosing quality seed is one of the most important steps in successfully planting or overseeding your lawn. If you don't know what to look for, you may be introducing unwanted intruders into that new stand. In particular, we are concerned with seed contaminated with orchardgrass and/or rough bluegrass (also known by its Latin name, Poa trivialis, or Poa triv for short). These are both perennial grassy weeds that cannot be selectively controlled once they are in a lawn. Orchardgrass is a problem because it is faster growing and lighter green than our turfgrasses. It is a bunch grass and so doesn’t spread, but infested areas are still unsightly due to small tufts of this species pockmarking the lawn. Rough bluegrass is fine-textured and forms circular patches in the lawn.

It blends in fairly well until summertime heat causes it to turn brown rapidly. If the rough bluegrass would just die in the heat, it would only be a temporary problem. Unfortunately, it usually just goes dormant, turning green again with cooler temperatures and rain.

Buying quality seed starts with knowing how to decipher the seed label. One of the most important things to look for is listed as "% other crop.” "Other crop" refers to any species that is intentionally grown for some purpose. That would include turfgrasses (those species other than the one you are buying) and pasture grasses. Orchardgrass and rough bluegrass both are listed as “other crop” seed.

Seed labels are required by law to show the percentage (by weight) of "other crop" in the bag, but unless a species constitutes 5% or more, the label doesn't have to list each species by name.

How much "other crop" is too much? That’s a difficult question to answer, but the tolerance is very low. It depends on what the "other crop" actually is, and the quality expectations of the buyer. In practice, "other crop" may refer to something relatively harmless, like a small amount of perennial ryegrass in a bag of tall fescue, or it may refer to something bad, like rough bluegrass or orchardgrass. The homeowner really has no easy way of knowing what the "other crop" is, although there are some hints. If it is something bad, less than ½ of 1% can ruin a bag of seed. Obviously, if your expectations are high for the area you are planting, you would want the "other crop" to be as close to zero as possible. Good quality seed will often have 0.01% “other crop” or less. (Ward Upham)

Fruit:
Fertilize Strawberries

An August application of nitrogen on spring-bearing strawberries is important in order to increase the number of strawberries produced next spring. Plenty of daylight and warm temperatures during June, July and August promotes the growth of new runner, or daughter, plants. As daylight hours dwindle and temperatures grow cooler in September and October, fruit buds for the next year's fruit crop develop. To get a good berry crop next spring, it is important for strawberry plants to be vigorous during this period of fruit bud development.

Nitrogen, applied mid August, will help promote fruit bud development. A general application rate is ½ to 3/4 pound of actual nitrogen per 100 feet of row. The nitrogen may be in the form of a fertilizer mixture such as ammonium phosphate or 12-12-12, or in a fertilizer containing only nitrogen such as urea or ammonium nitrate. Some specific examples would include:

         Iron + (11-0-0) at 6 pounds per 100 feet of row.
         12-12-12 at 5.5 pounds per 100 feet of row.
         Nitrate of Soda (16-0-0) at 4 pounds per 100 feet of row
         Ammonium sulfate (21-0-0) at 3 pounds per 100 feet of row
         Urea (46-0-0) at 1.5 pounds per 100 feet of row

On sandy soils, the rate may be increased by about a half. After spreading the fertilizer, sprinkle the area applying at least a half-inch of water to move the nitrogen into the strawberry root areas. (Ward Upham)

Pests:
What's the Buzz? Green June Beetles!

Just like Old Faithful erupts “on schedule” (well, on average, every 91 minutes), green June beetle flights predictably erupt in Kansas. So why are they worthy of comment? Because of their dark appearance, large size and the very audible buzz created by their wing beats, people often automatically become leery of their presence ---- the thinking being that these are bumble bees. Also, their rapid and erratic flights may result in accidental collisions, causing people to flee the area fearing that they will be stung. However, green June beetles are harmless ---- neither capable of biting nor delivering a sting. Rather than reacting “in fear of,” take the opportunity to capture a few beetles and admire them for their beauty from top to bottom.

Green June beetles sometimes are victims of mistaken identity ----that of being Japanese beetles. Size-wise, green June beetles are “Goliaths” compared to Japanese beetle “Davids.” There are distinct differences in color/color patterns as well as the presence or absence of white setal tufts. Lastly, green June beetles do not damage flowers or foliage as do Japanese beetles.

Probably the only legitimate complaint against green June beetles is that they may cluster on ripened (especially overly-ripe) fruit, notably peaches and grapes. Timely picking/harvesting of those commodities will help to avoid this situation. (Bob Bauernfeind)

Miscellaneous:
Field Dodder

Field dodder (Cuscuta campestris) is a unique parasitic annual plant that also is known as strangleweed or devils’ hair. It is composed of golden yellow "threads" that twine over other plants and attach themselves with short, suction-cup-like suckers that arise from the bottom of the dodder stems. These suckers penetrate the stems of host plants to obtain nourishment. Flowers are small, whitish, and 1/4 inch in diameter. They are produced from April to October and will produce a seedpod that is two-celled and four-seeded.

Because dodder is an annual, it must reproduce from seed. Plants present now will be killed by the first frost this fall. Seed may sprout in the spring or lie dormant for a number of years. Germination takes place in the soil, but roots die as soon as the plant finds an acceptable host. After attachment, dodder lives completely off the host plant. A single dodder plant can spread by branching and attacking additional host plants.

Destroying the host plants can control dodder, but this may not be an acceptable solution for many people. Dodder cannot be destroyed by pulling it off the host plants because remaining stem pieces will continue to grow. Trifluralin (Preen, Miracle-Gro Garden Weed Preventer, Treflan, Hi-Yield Herbicide Granules Weed and Grass Stopper) is a preemergence herbicide that can be used for control if applied before the dodder seed germinates. Also, glyphosate (Round-up, Kleen-up, Killzall, etc.) is effective on dodder. However, glyphosate is nonselective and will kill whatever it hits, including the host plants. (Ward Upham)

Contributors: Bob Bauerenfeind, Entomologist; Ward Upham, Extension Associate

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Horticulture Newsletter 2014, No. 31

8/5/2014

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Video of the Week:
When is Cantaloupe Ripe on the Vine?

Fruit:
When are Apples Ready to Pick?

Some gardeners would like to harvest apples early. Though nearly mature apples can ripen off the tree, there must be a certain level of maturity for this to happen. Here are some guides to help you decide when to pick your apples.

Color change: As apples mature, the skin color in areas of the stem and the calyx basin at the bottom of the apple turns from an immature green to a light-yellow color. Some apples will develop a red skin color before they are ripe, so this is not a reliable indication of maturity.

Flavor: This is a good guide if you are familiar with the apples you have and know how they should taste. Even if you do not know the characteristic flavor of the kind of apple you have, you can still sample slices of a few apples and decide if they have a sweet flavor. If they are not ready to harvest, they will taste starchy or immature. If apples have already fallen and taste a bit starchy, store them for a period to see if they become sweeter.

Flesh color: As apples mature and starches change to sugars, the flesh changes from very light green to white. When you cut a thin slice and hold it up to the light you can see the difference.

Days from bloom: The number of days from bloom is a reliable guide for general maturity time, but weather conditions will have some influence. Some kinds of apples and approximate days from bloom to maturity are Jonathan, 135, Delicious, 145, Golden Delicious, 145, and Winesap, 155 days. This process may be slower than usual due to the cooler weather this year.

Seed color: The seeds of most apples change from light green to brown as the fruit ripens. This indicator should be combined with other changes since it is not absolute. The flavor of the apples, the change in color of the stem and calyx basins and flesh color are important in deciding if apples are ready to harvest. (Ward Upham)

Vegetables:
Still Time for a Salad Garden

Plant salad crops such as lettuce, radishes, spinach, turnips, mustard and other greens from mid-August to early September for a fall harvest. Plant slightly deeper than you did in the spring. This will keep the seed slightly cooler though still warm and the soil should retain moisture longer. Water frequently (if needed) until seedlings start to emerge — which should be fast with our warmer soils. Watering heavy soils can sometimes cause a crust to form. This can be prevented by a light sprinkling of peat moss, vermiculite or compost directly over the row. Reduce watering frequency after plants emerge. Plants may need to be protected from hungry rabbits and insects. (Ward Upham)

Ornamentals:
Lilacs with Dead Canes

Lilac borers are insects whose larvae bore into stems usually during May and June. A sawdust-like material call frass is often seen around the base of stems after it has been pushed out the hole made by the borer. Canes often wilt and die during late summer especially if the summer has been dry. The larvae passes the winter inside the dead canes and pupates the following spring, usually during April. The adult, clear-winged moth resembles a wasp and often emerges during May through June though there is a great deal of variability. Eggs are laid on the stems of lilac, and the cycle starts over again. There is one generation in Kansas.

Though it is too late to spray for lilac borer this year, removal and destruction of dead canes will help reduce populations next year. You may also want to spray for the insect next spring. The first spray for ash/lilac borer should be applied when the Vanhoutte spirea is in full to late bloom, probably by about May 1. A second spray should be applied four weeks after the first. Thoroughly treat the lower portion of the stem of lilac or privet. Permethrin (Hi-Yield 38 Plus and Hi-Yield Garden, Pet, and Livestock Insect Control) are labeled for control. Though there are a number of other homeowner products that contain permethrin, the products listed above are the only ones I've found that specify how the material should be applied for borer control on the label. (Ward Upham)

Pests:
Plants and Lacebug Damage

We are seeing a number of tree and shrub species, including pyracantha and English oak, with browning or bronzing leaves due to lacebug damage. Woody plants that I have seen affected this year include oaks, hawthorns, cotoneaster and sycamore. Lacebugs are very small insects with wings that resemble lace under magnification. All stages of the insect develop on the undersides of leaves where they suck the sap. Adults are about 1/8-inch long. Under heavy infestations, stippling damage becomes evident. The leaves lose their green color, becoming pale and the undersides of the leaves may become speckled with brownish-black excrement spots and cast nymphal skins.

Healthy trees will not be damaged by lacebug this late in the season. The trees had plenty of time during the spring and summer to make the food needed to survive the winter. Control measures are not recommended. (Ward Upham)

Elm Leaf Beetle

There are normally two generations of this insect in Kansas with this being the second generation. All species of elms are attacked, but Siberian elms (often referred to as Chinese elms) are preferred.

Elm leaf beetles are serious nuisance pests of elms. Both adults and larvae feed on the elm leaves. Adult beetles are green-and-yellow striped and about 1/3-inch long. Young larvae are black and hairy but become yellow with two longitudinal dark stripes as they mature. The larvae cause most of the injury by window-feeding on foliage, resulting in a skeletonized appearance. Heavily infested leaves turn brown as if scorched by fire and often will drop prematurely. After several weeks of feeding, the larva crawl down the trunk or fall to the ground where they pupate. Elm leaf beetles overwinter as adults.

Active larvae can be controlled with a number of insecticides. However, check to make sure that larvae are still active before spraying. In many cases, the larvae have dropped from the trees and are pupating. Spraying is ineffective and unnecessary once pupation starts. Effective sprays for larvae (and adults) include carbaryl (Sevin), acephate (Acephate, Orthene), spinosad (Conserve; Captain Jack’s Dead Bug Brew, Borer; Bagworm, Leafminer & Tent Caterpillar Spray) lambda-cyhalothrin (Scimitar, Spectracide Triazicide, Bonide Beetle Killer). (Ward Upham)

Contributors: Ward Upham, Extension Associate

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2014 Horticulture Newsletter, No. 34

Video of the Week:
Overseeding your Lawn

Turfgrass:
Give Cool-Season Grasses a Boost

Power Raking and Core-Aeration

Flowers:
Peonies May be Cut Back Now

Ornamentals:
Big XII Gardening

Are Crabapples Safe to Eat?

Pests:
Yellowjacket Season is Here

Horticulture Newsletter 2014, No. 33

Video of the Week:
Grow Your Own Salad Mix

Turfgrass:
Overseeding a Lawn

Fall Lawn Seeding Tips

Flowers:
Dividing Daylilies

Fruit:
Pear Harvest

Vegetables:
Harvesting Winter Squash

Common Smut on Sweet Corn

Miscellaneous:
Pokeweed

Horticulture Newsletter 2014, No. 32

Video of the Week:
When is Watermelon Ripe on the Vine?

Turfgrass:
Recommended Tall Fescue Cultivars

Kentucky Bluegrass Variety Selection for Cool-Season Lawns

For Seeding Success, Pay Attention to "Other Crop" on the Seed Label

Fruit:
Fertilize Strawberries

Pests:
What's the Buzz? Green June Beetles!

Miscellaneous:
Field Dodder

Horticulture Newsletter 2014, No. 31

Video of the Week:
When is Cantaloupe Ripe on the Vine?

Fruit:
When are Apples Ready to Pick?

Vegetables:
Still Time for a Salad Garden

Ornamentals:
Lilacs with Dead Canes

Pests:
Plants and Lacebug Damage

Elm Leaf Beetle

Authors

Subscribe to the newsletter by entering your e-mail and clicking the link below

Archives

Categories

2014 Horticulture Newsletter, No. 34

Video of the Week:Overseeding your Lawn

Turfgrass:Give Cool-Season Grasses a Boost

Power Raking and Core-Aeration

Flowers:Peonies May be Cut Back Now

Ornamentals:Big XII Gardening

Are Crabapples Safe to Eat?

Pests:Yellowjacket Season is Here

Horticulture Newsletter 2014, No. 33

Video of the Week:Grow Your Own Salad Mix

Turfgrass:Overseeding a Lawn

Fall Lawn Seeding Tips

Flowers:Dividing Daylilies

Fruit:Pear Harvest

Vegetables:Harvesting Winter Squash

Common Smut on Sweet Corn

Miscellaneous:Pokeweed

Horticulture Newsletter 2014, No. 32

Video of the Week:When is Watermelon Ripe on the Vine?

Turfgrass:Recommended Tall Fescue Cultivars

Kentucky Bluegrass Variety Selection for Cool-Season Lawns

For Seeding Success, Pay Attention to "Other Crop" on the Seed Label

Fruit:Fertilize Strawberries

Pests:What's the Buzz? Green June Beetles!

Miscellaneous:Field Dodder

Horticulture Newsletter 2014, No. 31

Video of the Week:When is Cantaloupe Ripe on the Vine?

Fruit:When are Apples Ready to Pick?

Vegetables:Still Time for a Salad Garden

Ornamentals:Lilacs with Dead Canes

Pests:Plants and Lacebug Damage

Elm Leaf Beetle

Authors

Subscribe to the newsletter by entering your e-mail and clicking the link below

Archives

Categories

Video of the Week:
Overseeding your Lawn

Turfgrass:
Give Cool-Season Grasses a Boost

Flowers:
Peonies May be Cut Back Now

Ornamentals:
Big XII Gardening

Pests:
Yellowjacket Season is Here

Video of the Week:
Grow Your Own Salad Mix

Turfgrass:
Overseeding a Lawn

Flowers:
Dividing Daylilies

Fruit:
Pear Harvest

Vegetables:
Harvesting Winter Squash

Miscellaneous:
Pokeweed

Video of the Week:
When is Watermelon Ripe on the Vine?

Turfgrass:
Recommended Tall Fescue Cultivars

Fruit:
Fertilize Strawberries

Pests:
What's the Buzz? Green June Beetles!

Miscellaneous:
Field Dodder

Video of the Week:
When is Cantaloupe Ripe on the Vine?

Fruit:
When are Apples Ready to Pick?

Vegetables:
Still Time for a Salad Garden

Ornamentals:
Lilacs with Dead Canes

Pests:
Plants and Lacebug Damage