Crabgrass preventers are another name for preemergence herbicides that prevent crabgrass seeds from developing into mature plants. Many people have a somewhat foggy idea of how they work. They do not keep the seed from germinating but kill the young germinating plant.
 
Crabgrass preventers are just that – preventers. With few exceptions they have no effect on existing crabgrass plants, so they must be applied before germination. 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. If some products are applied too early, they may have lost much of their strength by the time they are needed. Most crabgrass preventers are fairly ineffective after about 60 days, but there is considerable variation among products. (Dimension and Barricade last longer. See below.)
 
For most of Kansas, crabgrass typically begins to germinate around May 1 or a little later. April 15 is normally a good target date for applying preventer because it gives active ingredients time to evenly disperse in the soil before crabgrass germination starts. However, this year, we may want to go a week or two early.  However, for southeast Kansas, this week would be more appropriate, and for northwest Kansas, mid-April would be best.
 
This year, it may be bet to base timing on the bloom of ornamental plants. The Eastern Redbud tree is a good choice for this purpose. When the trees in your area approach full bloom, apply crabgrass preventer. A follow-up application will be needed about 8 weeks later unless you are using Dimension or Barricade. Products that do require a follow-up application include pendimethalin (Scotts Halts) and Team (Hi-Yield Crabgrass Control).
 
Dimension and Barricade are the only two products that give season-long control of crabgrass from a single application. In fact, they can be applied much earlier than April 15 and still have sufficient residual strength to last the season. Barricade can even be applied in the fall for crabgrass control the next season.
 
Dimension can be applied as early as March 1. Because of the added flexibility in timing, these products are favorites of lawn care companies who have many customers to service in the spring. Though Dimension is usually not applied as early as Barricade, it is the herbicide of choice if it must be applied later than recommended. It is the exception to the rule that preemergence herbicides do not kill existing weeds. Dimension can kill crabgrass as long as it is young (two- to three-leaf stage). Dimension is also the best choice if treating a lawn that was planted late last fall. Normally a preemergence herbicide is not recommended unless the lawn has been mowed two to four times. But Dimension is kind to young tall fescue, perennial ryegrass, and Kentucky bluegrass seedlings and some formulations can be applied as early as two weeks after the first sign of germination. However, read the label of the specific product you wish to use to ensure that this use is allowed. Lawns established in the fall can be safely treated with Dimension the following spring even if they have not been mowed.
 
Note that products containing Dimension and Barricade may use the common name rather than the trade name. The common chemical name for Dimension is dithiopyr and for Barricade is prodiamine. Remember, when using any pesticide, read the label and follow instructions carefully.
 
We recommend crabgrass preventers be applied before fertilizer so that the grass isn’t encouraged to put on too much growth too early. However, it may be difficult to find products that contain preemergents without fertilizer. Those that don’t contain fertilizer are listed below. I didn’t find any products containing Barricade that did not also have a fertilizer. If anyone knows of other products that should be listed, let us know and we will publish them in a later newsletter.
 
Pendimethalin
- Scotts Halts
 
Team (Benefin + Trifluralin)
- Hi-Yield Crabgrass Control
 
Dimension
- Hi-Yield Turf & Ornamental Weed and Grass Stopper
- Bonide Crabgrass & Weed Preventer
- Green Light Crabgrass Preventer
​(Ward Upham)

We often are asked whether it is good to mow lower in the spring. The answer is yes and no. It doesn’t hurt to mow lower than normal the first mowing or two. As a matter of fact, it can actually speed green-up by removing old, dead grass and allowing the soil to warm up more quickly.  But the mowing height should be raised to normal after the first or second cutting to discourage crabgrass and encourage deep rooting.
 
Crabgrass seed must have light to germinate, and a high mowing height will help shade the soil. Also, root depth and mowing height are related on upright growing grasses such as tall fescue and Kentucky bluegrass — the higher the height of cut, the deeper the root system. A deeper root system means a more drought-resistant turf.
 
So, how low should you go on the first cutting? On tall fescue and Kentucky bluegrass, you can mow as low as 1 to 1½ inches. Be careful you don't go so low that you scalp the turf.   After that, raise the mowing height for Kentucky bluegrass to 2 to 3 inches but 3 to 3½ inches for tall fescue. (Ward Upham)

If you would like to have your tomato plants produce earlier in the year, there are certain things to keep in mind. Most people who try to get a jump on the season set their tomatoes out early and hope they do well. However, that is often not a good plan, as tomatoes have to have certain requirements before they will grow well. Those requirements are an acceptable soil temperature for root growth and an acceptable air temperature for both plant growth and fruit set.
 
Root Growth: Tomatoes need a soil temperature of at least 55 degrees to do well. Plastic mulch is  most commonly used to warm the soil. Several days may be needed to raise the soil temperature. Check the soil temperature 2.5 inches deep in the soil at about 11:00 a.m. If that is not possible, check the temperature before leaving for work and again when your return and use the average of the two. You may wish to lay a drip irrigation line before installing the plastic to make watering more convenient. See accompanying article on laying plastic mulch.
 
Air Temperature: Plants must be protected from frost. Hot caps or water teepees are placed over the young plants to provide protection as well as a higher average temperature to encourage growth. Eventually the plants will outgrow the cover and start to develop flowers. But if the temperature goes below 55 degrees at night, tomato flowers may not set. The plant is not hurt, but the blossom will not set fruit, or, if it does set fruit, the fruit is often misshapen.
 
How early can you transplant? Start with a date about 2 weeks earlier than normal. (Ward Upham)

Plastic mulch is sometimes used to start vegetables such as tomatoes and melons earlier than normal. Commercial growers use a machine to lay the mulch, but home gardeners must do this by hand. Following are some tips on how this is done.
 
1. Fertilize according to soil test. You won't be able to add fertilizer after the plastic is down.
 
2. Work the soil so that the bed can be easily shaped.
 
3. Use a garden hoe to form a trench along all edges of the plastic. The soil should be pulled to the outside of the bed. The trench should be formed six inches in from the edge of the plastic and extend along both sides and both ends. The trench should be deep and wide enough to bury six inches of plastic.
 
4. Lay trickle irrigation tube down the center of the bed. This isn't absolutely necessary but it makes it much easier to water. Overhead watering will hit the plastic and roll off.
 
5. Lay the plastic down and cover the edges with soil. You may need to slit the edge of the plastic where the trickle irrigation tube enters the end of the bed.
 
6. Plant when the soil temperature reaches the correct temperature for the crop (55 degrees for tomatoes and 60 degrees for melons) at a 2.5-inch depth. Check the temperature at about 11:00 a.m. to get a good average temperature. Check for several days in a row to ensure the temperature is stable. (Ward Upham)

Transplant solutions are mild fertilizer solutions that are applied to newly transplanted vegetables and flowers. Transplant solutions are also called starter solutions or root stimulators. Early-season plants not given a transplant solution often develop a purplish tinge to the leaves caused by a phosphorus deficiency. Surprisingly, the soil may have plenty of phosphorus but plants often have difficulty taking up nutrients in cool soils. The starter solution places soluble nutrients near the roots so the plants get off to a good, strong start.
 
Transplant solutions (root stimulators) are available for sale but it is also possible to make your own transplant solution from a fertilizer that contains more phosphorus than nitrogen or potassium such as a 5-10-5, 10-20-10 or 11-15-11. Mix 2 to 3 tablespoons of one of the above fertilizers in a gallon of water several hours before use. The fertilizer won't completely dissolve but enough will go into solution to get plants off to a good start. Use about 1 cup of transplant
solution for each transplant.
 
Sidedressing is a fertilization done after the plants are established. A fertilizer containing primarily nitrogen is used to keep plants growing and productive. Nitrate of soda (16-0-0) is often used at the rate of 2 pounds fertilizer per 100 feet of row. More commonly available lawn fertilizers such as a 30-3-3, 29-5-4 or something similar can also be used but cut the rate in half.
 
Be sure any lawn fertilizer used does not contain weed preventers or weed killers. Note that most fertilizers weigh about 1 pound per pint of product.  We have a sidedressing sheet available that lists crops, rate of fertilizer application and timing of application(s) for many common vegetables as well as annual flowers. The sheet can be viewed at  http://www.hfrr.ksu.edu/doc1991.ashx   (Ward Upham)

Most of the soil tests we receive for vegetable gardens are high in phosphorus and potassium, leaving nitrogen as the nutrient needed most. However, many of our organic fertilizers contain similar amounts of all three nutrients. So, what can we use that provides more nitrogen than phosphorus and potassium? Following is a short list of such fertilizers.
 
 

​
Product                               Analysis                   Pounds/ 100 sq ft                       Notes
Blood Meal                                      12-0-0                                              5 - 10                          Can burn plants if overapplied
Cottonseed Meal                         6-0.4-1.5                                            10                               May have pesticide carryover
Soybean Meal                                  7-2-1                                                  8
 
Feed stores will often sell these products. Colorado State University has an excellent publication on organic fertilizers at  http://www.ext.colostate.edu/mg/Gardennotes/234.html  (Ward Upham)

​Contributors:  Ward Upham, Extension Associate

RetailWorks
February 4, 2016
Manhattan, KS
 
Grow Your Garden Center Business in 2016!
We hope you'll join us for this companion conference to the biennial NurseryWorks conference--RetailWorks on Thursday, February 4, 2016 in Manhattan. While NurseryWorks focuses on providing resources for wholesale nursery crop growers, RetailWorks is designed with the independent garden center's needs in mind. We continue to bring in outstanding national and local speakers on a variety of topics. You'll find great content and networking at RetailWorks 2016--get it on your calendar and register today!  For more information, go to:
http://retailworks.weebly.com/ or register online at https://2016retailworks.eventbrite.com

Late spring frosts often eliminate potential peach crops in Kansas.  Since hardiness of fruit buds drops dramatically as flower buds open, even a delay in bloom time of a few days can dramatically affect the size of fruit crop.  A study done in southwestern Idaho investigated the average bloom times of a number of peach cultivars from 2003 - 2007.
 
Cultivar                    Date of full bloom
‘Snow Giant’                April 5
‘Jupiter’                        April 7
‘Yukon King’                April 7
‘Burpeach Six’             April 7
‘Fairtime’                      April 7
‘Coral Star’                   April 7
‘July Sun’                     April 7
‘Zee Lady’                    April 7
‘May Sun’                    April 8
‘Crimson Lady’           April 8
‘Summer Flame’         April 8
‘Elegant Lady’             April 8
‘Sugar Giant’               April 8
‘July Flame’                 April 8
‘Sweet Dream’             April 8
‘August Flame’            April 8
‘September Snow’       April 8
‘Snow King’                  April 8
‘Star Fire’                      April 8
‘Saturn’                         April 8
‘August Lady’              April 9
‘Ryan Sun’                    April 9
‘Brenda Sun’                April 9
‘All Star’                       April 9
‘Autumn Red’              April 9
‘O’Henry’                     April 9
‘Opal Moncav’             April 9
‘Rich Lady’                   April 9
‘Vista’                            April 9
‘Glow Star’                   April 9
‘Summer Lady’           April 10
‘Red Star’                     April 11
‘Fancy Lady’                April 12
‘Sierra Gem’                April 12
 
'Intrepid,' though not included in the above study, is a cultivar not only known for its late bloom time but also its frost-resistant blooms.  A study done in North Carolina noted that exposure to 6 consecutive subfreezing nights at 50% bloom did not eliminate the fruit crop.  All flower buds on all check cultivars were killed. (WU)

We occasionally receive calls from gardeners who want to know how to treat an apple seed so it will germinate. Usually, the gardener is trying to reproduce an old apple tree that was special for some reason (good quality fruit, planted by grandparents, etc.).  Unfortunately, apples grown from seed will not be like the parent. About 1 in every 80,000 apple trees grown from seed will be as good as the apples we are used to eating. Apple trees grown from seed usually have small and inferior quality fruit.
 
If you want a tree exactly like the parent, you must propagate that tree vegetatively. In the case of apples, this usually means grafting. Apple trees are actually quite easy to graft, even for novices. Don't be afraid to try even if you haven't grafted before. The step that needs to be done at this time of year is the choosing and cutting of scion wood or small branches that will be grafted on top of a rootstock.
 
See the accompanying article in this newsletter on how this is done. However, if you don’t have an existing tree to graft onto, you will need to plant a rootstock this year for grafting onto next. Fruit trees are normally grafted (or budded) onto specially selected rootstocks. These rootstocks usually reduce tree size. For example, a tree that normally would reach 25 feet tall will only reach 10 feet if it is grown on a certain rootstock. Dwarfing rootstocks also allow apples to bear fruit a year or more earlier.
 
A tree on its own roots normally takes 5 to 7 years before it will bear. Semi-dwarf trees bear in 4 to 5 years, and dwarf trees bear in 3 to 4 years. Unfortunately, not all dwarfing rootstocks are well adapted to Kansas. Semi-dwarf trees usually are a better choice for us. Note that rootstock reduces tree size, not fruit size. Therefore, a Golden Delicious tree that only reaches 8 feet tall due to a dwarfing rootstock, will bear the same size fruit as a Golden Delicious tree that is 25 feet tall.
 
Most nurseries only sell trees that are already grafted. A company that does sell rootstocks is Raintree Nursery, Morton, WA, (360) 496-6400, http://www.raintreenursery.com/Rootstocks/ Another is Cummins Nursery, 865- 233-3539, http://www.cumminsnursery.com/rootstocks.htm though there is a minimum shipping and handling fee of $20.
 
It is also possible to buy a tree from a local nursery and graft your clone into it. This will give you one tree that produces two different apples. One disadvantage of this method is that it is possible to prune off the special clone by mistake in later years.

This information does not include the details of grafting or budding or subsequent care.  The Missouri Extension Service has an excellent publication on grafting at http://extension.missouri.edu/explorepdf/agguides/hort/g06971.pdf   as well as a second publication on budding at http://extension.missouri.edu/explorepdf/agguides/hort/g06972.pdf . Be sure to practice your cuts on wood you prune off in March. After you do about 100 cuts, you will start to get the hang of it. (Ward Upham)

If you start vegetable plants indoors, it is often helpful to list seeding dates on a calendar so that plants are ready for transplanting at the proper time. To do this, choose your transplant date and count back the number of weeks necessary to grow your own transplants. For example, cabbage, broccoli, and cauliflower are usually transplanted in late March to early April. It takes 8 weeks from seeding to transplant size.
 
Plants should be seeded in early February. Information on how many weeks it takes to grow transplants is available in our January 6 newsletter at  http://www.hfrr.ksu.edu/doc4036.ashx
 
Below are examples of some common vegetables grown for transplants and a recommended date for seeding. Dates are Saturdays as this is when many homeowners have the most free time. The dates are not set in stone, and a week earlier or later will not ruin the plants. Also, you may want to seed a week or two earlier if you are in southern Kansas and possibly a week later if you are in northern Kansas. Keep notes on how well the transplants did so you can tweak the
planting schedule. Your conditions may result in plants that need a bit more or a bit less time. (Ward Upham)
 
Crop                                                      Seeding Date        Transplant Date
Cabbage, broccoli, cauliflower        February 6            April 2
Lettuce (if your grow transplants) February 6            April 2
Peppers                                                March 19               May 14
Tomatoes                                             March 26              May 7

Miniature roses are dwarf versions of roses including the classic hybrid teas. Though they are much smaller (12 to
15 inches tall or less), they are surprisingly tough and can be planted outside where they will survive our Kansas winters if mulched. However, many gardeners like to grow the miniatures indoors where they can enjoy them during the drab winter months.

Miniature roses grown as houseplants have specific requirements. For long lasting flowers, air should be moist with a relative humidity of 50 to 60 percent preferred though 40 percent is adequate. Placing the pots on a tray that holds moist pebbles will help provide the humidity needed.
 
Like most plants, roses need a lot of light in order to flower. Though miniature roses will survive in a south window, many people will supplement available light with fluorescent lamps. Timers can be used to automatically turn the lights on and off. Providing 14 hours of light per day will be plenty for roses to grow and flower. Lights are normally spaced 3 to 4 inches above the tops of the plants.
 
Probably the most serious pest of these plants indoors is spider mites. These mites are very small but can devastate miniature roses. They like dry, warm conditions. Maintaining adequate relative humidity levels and washing the plants once a week in tepid water will help prevent problems. If mites do develop, try using an insecticidal soap or horticultural oil (2 percent rate) for control. The horticultural oil will probably be more effective than the soap. Be sure to spray or wash the entire plant including the underside of the leaves so that all mites are contacted.
 
Miniature roses can be placed outdoors during the summer to take advantage of higher light levels. Do not place the plant in full sun immediately but gradually grant more light over a period of several weeks. Pots sunk in the ground will not need to be watered as often as those exposed. Turn the pot 180 degrees every couple of weeks to break off any roots that escape the pot and move into the underlying soil.
 
Miniature roses are not the easiest plants to grow as houseplants but can be well worth the effort required. (Ward Upham)

If you have had trouble finding a listing of plants recommended for Kansas, visit our web page devoted to this topic. We have links to a wide variety of plants including annual flowers, perennial flowers (including breakouts for iris and daylilies), fruit, vegetables, turfgrass, low-maintenance roses and tree recommendations that are broken out by areas of the state. We also list recommended low water use plants. You can find this page at http://www.hfrr.ksu.edu/p.aspx?tabid=731
 
We also have images of hundreds of the following:
 
Varieties of iris and daylilies found in the University Gardens Collection Gardens at http://www.ksre.ksu.edu/ksugardens/p.aspx?tabid=38
 
Annual flowers recommended for Kansas at  http://www.prairiestarflowers.com/Prairie_Star_nav.html
 
Perennial flowers at  http://www.prairiestarflowers.com/Prairie_Bloom_nav.html   (Ward
Upham)
 
Contributors:  Ward Upham, Extension Associate