July - Aug
2017
Disease Management in the Home Lawn
By Adam Leonberger
Numerous infectious diseases can occur on lawns in Kentucky. Unless diagnosed and managed, these diseases can sometimes cause extensive damage. A sound lawn management program provides benefits in two ways: it reduces the severity of lawn diseases; and improves the lawn’s recovery should a disease outbreak occur. You can control diseases of turfgrasses most effectively by using as many of the following lawn management practices as feasible. The first step in improving your lawn is to accurately diagnose the problem. Although diseases are sometimes responsible for poor turf quality, they are not the only cause. You may need to consider some other possible causes of thinning or dead grass: improper fertilization, chemical injury, mower problems, dog or insect injury, localized dry spots, poor soil drainage, excessive thatch, and competition from other plants. Bring samples of diseased turf into the Extension Office for assistance. Underfertilization makes certain diseases worse, whereas overfertilization worsens others. For greatest lawn health, make sure your program provides moderate fertility. Lawns of Kentucky bluegrass, tall fescue, or perennial ryegrass should receive no more than three to four pounds of total nitrogen per 1,000 square feet each year; even less nitrogen is acceptable for lawns on a low-maintenance or moderatemaintenance program. Most or all of the fertilization should be applied during the fall months, which helps to promote recovery of the grass in the event a summer disease outbreak has already occurred. Avoid heavy applications of fertilizers during spring and summer, as lush spring or summer growth can be more prone to certain diseases. Also, have the soil tested to determine whether lime, potash, or phosphate should be applied to meet your lawn’s fertility needs.
Mowing too closely during the hot months of summer can stress the lawn, increasing susceptibility to diseases and environmental extremes. Mow lawns at a 2- to 2 1/2-inch height. Mowing too high can also favor some diseases, particularly in the late autumn. Continue mowing through late autumn to prevent leaf tissue from accumulating. A thick covering of leaves on the lawn during the autumn and winter can lead to outbreaks of disease during wet weather even though the grass is dormant. Keep the mower blades sharp. A dull mower shreds the grass blades. This not only causes the lawn to be temporarily unsightly, but it may also provide wounds for infectious fungi to invade. Avoid frequent, light waterings of your lawn. This encourages the grass to develop a shallow root system and frequently provide the moisture that fungi need to infect the leaves. When watering, saturate the soil to a depth of three to four inches to promote deep rooting. If a disease outbreak is evident, water early in the day so that the leaves dry by nightfall. If the lawn is watered late in the day, the leaves may remain wet until morning, thus providing long periods of leaf wetness favorable for infectious fungi. Control weeds, insects, and other lawn pests which can cause stress. A stressful turfgrass environment often favors diseases. Follow all label directions when using lawn chemicals, as improper application can sometimes lead to turfgrass injury. Fungicides can be an important part of a disease-control program in an intensively managed turf, such as putting greens on a golf course. However, if you follow a sound program of lawn management through the practices described above, rarely should you need fungicides for a home lawn. Before using any fungicide, be sure the disease is properly diagnosed. If a disease breaks out in your lawn, keep in mind that a return to weather favorable for turf growth and vigor will help alleviate the problem.
es so the plants can ze cool season grass speci tili fer to e tim e on er mb g green-up. Fall is the nu roots. This will aid in sprin ir the in s ate dr hy bo car of ements. Now is develop a strong reserve on soil tests and plant requir sed ba be ld ou sh es rat ion sion office. Fertilizer applicat ts to your local county exten tes il so n law e tak to e tim the perfect
Planting Fall Vegetables
Fruit & Veggie Garden
2
in Kentucky By Rick Durham
It’s not too late to continue to enjoy your garden and to add new plantings. You can grow a variety of produce in Kentucky gardens in the coming weeks and have several fresh items available well into the fall. Cooler nights later in the year can increase the sugar content of many crops and thus increase their quality. Cooler nights also slow growth, so your crops can take longer to mature than in the summer. Keep this slower pace in mind when you check seeds for days to maturity. Early August is the right time to make your last planting of bush beans, carrots, sweet corn, kale, collards, bibb lettuce, turnips, and cole crops such as kohlrabi, Chinese cabbage, Brussels sprouts, cabbage, cauliflower and broccoli. For late August and into September you can try planting mustard greens, spinach greens, radishes, turnip greens and leaf lettuce. Before planting, remove any existing debris, including crops and weeds from your garden bed, move them to the compost bin and then prepare the soil.
If the previous crop was well fertilized and grew vigorously you may not need to add much, if any additional fertilizer, otherwise apply about 2 to 3 pounds of a complete fertilizer such as 5-1010 or 10-10-10 per 100 square feet of planting area. Remember to keep fall gardens well watered as this tends to be a fairly dry time in Kentucky. A weekly irrigation sufficient to wet the soil to 6 or 8 inches should be adequate. This is more or less equivalent to a weekly 1-inch rain. To learn more about fall gardening options, contact your local Cooperative Extension Service and ask for publication ID-128, “Home Vegetable Gardening in Kentucky.” You may also view the publication online at http://www2.ca.uky.edu/agcomm/pubs/ id/id128/id128.pdf
ity than its peers, or rated r number of days to matur rte sho a ve ha t tha ies iet calculation, since Select vegetable var te, but add extra time to the da st fro m fro ck ba t un Co to produce for late-season growing. mature. Don’t expect them nts pla l fal as ler coo d an r rte days are getting gradually sho ing springtime days. en gth len , ing as fast as in warm
Flowers
3
Good Perennials for Beginning Gardeners By Amy Aldenderfer
When starting a new hobby, there are tools to acquire, techniques to learn and materials to purchase. This is so true for flower gardening. The tools can be as simple as a trowel and a watering hose and as complex as irrigation systems and robotic lawn mowers. But for the beginning gardener, the vast variety of flowers, trees and shrubs can be overwhelming. (It still is for me, and I’ve been gardening for almost 40 years!)
Where do you start choosing the plants that you are going to grow in the flower beds? Starting with a plan before heading to the nursery or garden center is the best option. Knowing the garden “stats” will definitely narrow the plant choices. Your garden stats are: sun or shade, well-drained soil or soggy, size of the area, and hardiness zone.
Once you have the information in hand, check out your local Extension Service’s plant lists. The University of Kentucky breaks their perennial plant lists into “Perennials for Sunny Locations” (HO-76) and “Perennials for Shady Locations” (HO-77).
2017 Perennial plant of the year- Asclepias tuberosa
The other list that I would recommend is the Perennial Plant of the Year. They are found at perennialplant.org. Since 1990, the Perennial Plant Association picks one plant a year to be promoted as the Perennial Plant of the Year. Their goal is “to showcase a perennial that is a standout among its competitors. Perennials chosen are suitable for a wide range of growing climates, require low maintenance, have multiple-season interest, and are relatively pest/disease-free.”
Finally, pick a plant that fulfills a requirement for the garden. It could be the flower color, the height, the scent, or because it jumped in your cart and said, “Take me home!”
cloudy and cool day, if Plant the perennials on a Make sure to give them possible, to avoid shock. triple in size. As perennial sufficient space to double or e any spent blossoms by garden plants bloom, remov th your fingers. simply pinching them off wi
Trees & Shrubs
Trees & Iron Chlorosis
4
By Kelly Jackson
If the leaves of your trees or shrubs are turning pale green, yellow, or white, but have much darker green veins, they may be experiencing iron chlorosis. Iron is a necessary element for the development of chlorophyll. Chlorophyll is what gives leaves their green color and is the source for the plant’s food and energy. When iron is insufficient for normal growth, yellowing leaves may occur. These symptoms may appear over the entire tree, on one side only, or be limited to an individual branch. Iron chlorosis is common in pin oak, white oak, silver maple, crabapple, white pine, magnolia, holly, sweet gum, dogwood, azalea and rhododendron. Iron chlorosis may occur as the result of several causes including: 1. High pH: Iron is more soluble and available to plants at a soil pH range of 5.0 to 6.5. When pH is higher than 6.5, due to the application of excessive amounts of lime or phosphates to the soil, other elements interfere with the absorption of iron, even though it may be present in the soil. This condition worsens when large amounts of copper, manganese, or zinc is present or there is high soil moisture. Ammonium sulfate or sulfur may have to be applied to lower the pH levels. 2. Over-watering or poor drainage: Trees need 1 inch of water per week. Adjust your watering times so that you water less frequently but for
a longer period of time to encourage deep rooting. Poor drainage may also be a problem in urban plantings where original topsoil has been replaced with subsoil. You may need to correct this problem by installing tile lines near valuable trees. 3. An actual deficiency of iron: If the tree or shrub is not exhibiting symptoms related to high pH or water, then there may be an actual iron deficiency. There are three ways to provide iron to the plants: foliar application, soil treatment or trunk injection. Foliar application uses a spray of iron sulfate or iron chelate solution. It provides quick results but is short-lived and requires repeat applications. Adding iron to the soil has a much slower response, but can prevent iron deficiency for 3 to 4 years. The rate of iron sulfate varies by tree size. Contact your Extension agent for specific application instructions. Trunk injections have been found to be effective under specific conditions although results may vary with tree species, severity of chlorosis, time of year, soil moisture and individual tree response. Homeowner trunk injection systems are available, however commercial arborist have access to even more systems and the experience of application.
Weeds and grass that grow too close to your tree can ste al water and nutrients, and damage from lawnmowers lead to . Make sure your tree is pr operly mulched using the leave 3 inches of free space 3-3 -3 rule: around the trunk for air ex change, spread the mulch in shape 3 feet from the trunk a do nut to keep down weeds and gra ss growth, and pile the mu inches high to keep the roots lch 3 from drying out too quick ly.
Pests You Can Control Corn
5
Earworm in Sweet Corn
By Ric Bessin
One of the most potentially damaging problems facing sweet corn producers is controlling insects that feed on the ear. During the summer months, if you grow sweet corn, you need to watch for corn earworm. Earworms are moderately hairy larvae that vary in color from yellow to green to red to brownishblack, but they all have a brown head without markings and numerous microscopic spines covering their body. You may find them feeding in the ear tips following silking. The larvae are cannibalistic, rarely is there more than one per ear or whorl. Corn earworm is potentially the greatest threat to sweet corn production in our state. Because it feeds directly on the ear, is difficult to control and is common in high numbers at the end of the season, most insecticides used on sweet corn target this pest. Once earworm becomes established within the ear, controlling it is impossible. Earworms spend a relatively short period of their life feeding in a site that can receive an adequate insecticide application. An effective program, especially for corn planted later in the season, is necessary to ensure a minimal amount of damaged ears. Currently, the primary insecticides used for corn earworm control in sweet corn belong to the pyrethroid class. There is concern that corn earworm in some regions of the Midwest has developed resistance to this class of insecticides. Some field failures have been reported.
You can start a preventive program against corn earworms when 10 percent of the ears are silked. Repeat sprays at three-to-five-day intervals until 90 percent of the silks have wilted. This strategy should give a high percentage of worm-free ears during early and midseason. Control is more difficult late in the season. Even shortening spray intervals may produce only 90 percent clean ears. For more information on sweet corn pest control, contact your local Cooperative Extension Service or check out the University of Kentucky Department of Entomology website about corn earworm control at http://www.ca.uky.edu/entomology/entfacts/ef302.asp.
n is very important. Sweetcorn variety selectio g, tight fitting shuck Corn hybrids having a lon age than those with appear to suffer less dam tor determining the loose shucks. The key fac m attack is planting relative risk of corn earwor typically have fewer date. Early and midseason we eggs on the silks. corn earworm moths to lay
Upcoming
Horticulture Events JULY July 8 Master Gardener Promotion 270-388-2341 Lyon County Farmers Market (Kuttawa) July 10 Flower Arranging 859-572-2600 Campbell County Extension Office (Highland Heights) July 11 Landscape Plants for Shade 270-821-3650 Hopkins County Extension Office (Madisonville) July 13 Weed Management for the Landscape and Vegetable Garden 859-572-2600 Campbell County Extension Office (Highland Heights) July 14 Invasives in the Forest and Landscape 606-376-2524 Cumberland Falls State Resort Park July 18 Managing Perennials through Pruning 859-873-4601 Woodford County Extension Office (Versailles) July 24 Leaf Casting and Concrete Pots Workshop 270-388-2341 Lyon County Extension Office (Eddyville) AUGUST August 1 Gardening and Your Health 270-821-3650 Hopkins County Extension Office (Madisonville) August 1 Flower Arranging Class https://www.facebook.com/pg/marshallcountyanr/ events/ Marshall County Extension Office (Benton)
Upcoming Events
6
August 10 Water Garden Management 859-572-2600 Campbell County Extension Office (Highland Heights) August 12 Woodland Owners Short Course 606-864-4167 Laurel County Extension Office August 15 Common Yard Tree Problems 859-873-4601 Woodford County Extension Office (Versailles) August 21 Saving Seeds (606) 564-6808 Mason County Extension Office (Maysville) August 24 Toxic Plants 859-572-2600 Campbell County Extension Office (Highland Heights) SEPTEMBER September 5 Cool-Season Vegetables 270-821-3650 Hopkins County Extension Office (Madisonville) September 5 Forest-farmed Herbs 859-356-3155 Kenton County Extension Office (Covington) September 8 Spring Flower Pots with Bulbs and Pansies 270-388-2341 Lyon County Extension Office (Eddyville) September 12 Growing PawPaw Trees 859-572-2600 Campbell County Extension Office (Highland Heights)
Upcoming
Horticulture Events SEPTEMBER CONT. September 14-15 2017 Kentucky Master Gardener Conference Scott County Extension Office (Georgetown) September 16 The Giant Pumpkin and Watermelon Weigh-Off 270-422-4958 Roberts Family Farm (Guston) September 16 Farm Harvest Tour 859-356-3155 Kenton County Extension Office (Covington) September 19 Fall Wildflower Walk 859-356-3155 Kenton County Extension Office (Covington) September 19 Home Lawns 859-873-4601 Woodford County Extension Office (Versailles) September 23 Woodland Owners Short Course 859-356-3155 Kenton County Extension Office (Covington) OCTOBER October 5 Beginning Composting 859-356-3155 Kenton County Extension Office (Covington) October 5 Invasive Plants and Insects in the Woods and Landscape 859-356-3155 Kenton County Extension Office (Covington) October 17 Nuisance Wildlife 859-873-4601 Woodford County Extension Office (Versailles)
Upcoming Events
October 19 Chainsaw Safety 859-356-3155 Kenton County Extension Office (Covington) NOVEMBER November 6 Native Trees and the Insects That Love Them 859-356-3155 Kenton County Extension Office (Covington) November 9 Thanksgiving Door Swag 859-356-3155 Kenton County Extension Office (Covington) November 21 Winterizing your Garden 859-873-4601 Woodford County Extension Office (Versailles) DECEMBER December 7 Evergreen Holiday Swag 859-356-3155 Kenton County Extension Office (Covington) December 19 Wreath-making with Fresh Greenery 859-873-4601 Woodford County Extension Office (Versailles)
7