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Video of the Week: Spider Mites on Tomatoes
https://kansashealthyyards.org/all-videos/video/spider-mites-on-tomatoes
REMINDERS
• Seed beets, carrots and beans
• Never fertilize warm-season grasses such as zoysia, bermuda and buffalo after August 15
• Remove sucker growth and watersprouts from fruit trees, especially apples
Prioritizing Water in the Landscape
During periods of drought, it may be necessary to prioritize which plants will be first in line to receive supplemental water due to time and water restrictions. As with many decisions, cost plays a major role in determining where to begin watering.
Start with the large, established trees. These are the most difficult and expensive to replace if they don’t survive. They also take the longest to become established. While they may not require supplemental water during a short drought period, if it becomes prolonged established trees can still suffer. Next, care for the young trees which are still developing their root systems.
Take care of shrubs next, followed by perennials, lawn and finally, annuals. This order will direct your attention to the plants that have had the most invested in them saving you time and money if you must replace plants that don’t survive. (Cynthia Domenghini)
Watering Newly Planted Trees and Shrubs
Young trees and shrubs have not established the root system necessary to survive extreme heat and dry spells without supplemental water. After planting, it is essential to keep the root ball area moist for several weeks, but even a couple years later it may be necessary to periodically apply water to the area.
Give newly planted trees 10 gallons of water weekly. Apply the water slowly so it can sink deep into the root zone and promote new growth. Build a reservoir, about three to four-inches tall around the tree to keep the water in the desired area. Alternatively, drill a 1/8-inch hole in a plastic 5-gallon bucket. Place the bucket beneath the tree and fill with water. After it has drained fill it a second time. When it has emptied, the tree will have received ten gallons. There are also bags available commercially that serve a similar purpose. They can be secured to the tree and filled with water which then slowly enters the soil. Mulch is recommended to help retain moisture, moderate soil temperature and prevent damage to the trunk from lawn mowers and other tools. (Cynthia Domenghini)
VEGETABLES
Green Beans Producing Flowers but not Beans
Though relatively easy to grow, green beans may not produce efficiently when adequate growing conditions are not met.
Temperature is a key factor that affects bean production. High (above 85 degrees F) or low (below 70 degrees F) can cause plants to create flowers but no beans.
Periods of dryness between watering can also inhibit bean development. Hot, dry winds can exacerbate this problem.
The best way to ensure a healthy bean crop is proper crop management. Use mulch to regulate soil temperature and retain moisture. Plant a windbreak crop such as corn to shield green bean plants. Harvest beans regularly to encourage the plants to continue producing. If beans are left on the plant beyond their peak harvest time they will use energy to develop seed rather than create new beans. (Cynthia Domenghini)
FRUIT
Watering Fruit Plants During the Summer
Monitoring soil moisture of fruit crops is important to preserve the quality of the harvest. Allowing fruit crops to be under heat or drought stress during fruit development restricts cell division. This directly affects the size of the mature fruit even if additional water is added later. Drought stress can also lead to wilting and yellowing leaves as well as leaf and fruit drop. Next year’s crop could be affected too as buds may fail to develop.
The takeaway message is to monitor the soil at the rootzone to ensure proper moisture levels. This can be done by pushing a probe into the soil. A wooden dowel, rebar or even a screwdriver can work for this task. Try to insert the probe at least 8 to 12 inches. Dry soil will be very difficult to penetrate indicating water should be applied.
Add water slowly to the rootzone using a sprinkler, soaker hose, drip irrigation or other method. The amount of water necessary will vary depending on plant size, but use the soil probe as your indicator. When the probe can reach 12-inches into the soil, the moisture level should be adequate.
Monitor fruit crops weekly during hot, dry weather. Newly planted fruit crops and strawberries, with shallow root systems, will need to be checked at least twice a week for soil moisture. (Cynthia Domenghini)
TURF
Should I Water My Lawn?
We have been receiving questions recently on whether to water lawns, especially the cool-season lawns tall fescue and Kentucky bluegrass. Tall fescue and Kentucky bluegrass can go drought dormant for 6 to 8 weeks without harm. Therefore, some homeowners allow their lawn to go dormant during summers such as this. However, when the rains return, the grass will be thin and weeds may become a problem. The weeds can be controlled but that adds an additional expense. Also, if we reach that 6-week period, the grass needs to be given 1/4″ of water a week to keep the crown hydrated so the turf doesn’t die.
If your lawn has been dormant for a while and are wondering if the turf is still alive, pull up an individual plant and separate the leaves from the crown. The crown is the area between the leaves and the roots. If it is still hard and not papery and dry, the plant is still alive.
If you want to keep the grass going through the summer, wait until you see spots in the lawn turn a purplish hue and then water well so the soil is moist about 6 inches deep. Continue to do this until the rains return. Of course, watering more won’t hurt except for your water bill. (Ward Upham)
Crabgrass Control
You may have noticed a lighter green, low-growing grass amongst your lawn. Crabgrass tends to make its appearance this time of year, particularly in areas where the lawn is less dense. Identified by the wide, flat blades, crabgrass is a warm-season annual. It dies back either after flowering and setting seed or with the first hard frost. However, it is very efficient at reproduction leaving behind thousands of seeds to invade the lawn next year. Though not particularly harmful, when it dies back in August large sections can leave unsightly bare spots in the lawn. Fortunately, cool-season grasses should also begin to flourish this time of year so if the crabgrass infestation is minimal, treatment is not necessary.
Aside from manually removing plants, crabgrass can be difficult to control once it has germinated. Therefore, prevention is the best approach for controlling crabgrass. Maintaining a thick, healthy lawn will prevent crabgrass seeds from germinating. Mow your lawn no shorter than three-inches which will help prevent sunlight from reaching the seeds on the soil surface. Around mid-April apply a pre-emergent to combat seeds from the previous growing season.
At this point in the season, it is too late for a crabgrass preventer. If manual removal is not an option there are some herbicides that will kill crabgrass plants including: Ortho Weed-B-Gon Max + Crabgrass Control, Fertilome Weed-Out with Crabgrass Control, Monterey Crab-E-Rad and BioAdvanced Lawn Weed & Crabgrass Killer. Each contains quinclorac, which is a crabgrass herbicide, as well as other active ingredients that control broadleaf weeds. Quinclorac is an excellent crabgrass killer that controls not only crabgrass but also has good activity on foxtail and certain broadleaves such as field bindweed, black medic and clover. However, it does little to nothing to goosegrass. If you use crabgrass killer on your lawn bag the clippings. Do not use them as mulch or in compost. (Cynthia Domenghini)
PESTS
Cicada Killer Wasps
Description: At about 1 ½-inches long, cicada killers are an intimidating wasp. They have reddish colored wings and legs and a black abdomen with wide, yellow stripes. Cicada killers live independently though nests may be relatively close to each other. Females have a stinger which is used to paralyze their prey. They rarely sting people unless agitated. Males are smaller and do not have a stinger.
Females are responsible for locating cicadas and paralyzing them with their stinger. She then carries the cicada back to her burrow. Each burrow can house up to 20 cicadas.
Life Cycle: Adult females lay a single egg on each cicada they drag into the ground. Eggs hatch in two to three days into legless, white grubs which feed on the cicada. The larvae then create a protective case in which to overwinter. Adult wasps die in early fall. In spring the larvae pupate in the pupal cases and emerge as adults in June/July. There is one generation per year of cicada killers.
Damage: Cicada killers typically cause very little damage to the landscape. A heavy infestation may become a nuisance as they protect their nests. The burrows may be considered unsightly, especially in a lawn area.
Control: Cicada killers prefer well-drained, light soils in full sun. They may burrow along sidewalks or flowerbeds but do not like areas covered with mulch. Maintaining a thick, healthy lawn is the best control for preventing burrows. Pesticides are not usually necessary since adults are only present for about two months beginning mid to late summer, but Permethrin may be used for control. Treat the burrows at dusk when females have returned. Males are often found perched nearby. Products with permethrin include:
(Dusts) Eight Garden Dust – Bonide, Multipurpose Garden and Pet Dust – Green Thumb Garden, Pet & Livestock Dust – Hi-Yield
(Liquids) 38 Plus Turf, Termite & Ornamental Insect Spray – Hi-Yield, Eight Vegetable, Fruit & Flower Conc. – Bonide, Eight Yard & Garden RTS – Bonide, Garden and Farm Insect Control- Hi-Yield (Cynthia Domenghini)
MISCELLANEOUS
Wood Chips as Mulch
Mulching the landscape is a recommended practice to moderate soil temperature and moisture and prevent weeds. Wood chips created by tree trimming companies can be an inexpensive way to mulch around trees and shrubs in the landscape. Homeowners have some concerns about the effect green wood chips may have on their landscape plants.
Will using fresh wood chips as mulch deplete nitrogen from the soil? Microorganisms found in the soil break down organic matter using nitrogen from the soil. Wood chips are very low in nitrogen so more is pulled from the soil to break down the wood chips making the nitrogen less available for the desired plants. However, when used only on the surface as a mulch, this is not a concern. It is not recommended to incorporate fresh wood chips into the soil. Recognize the difference between mulch and compost.
Will wood chips from a diseased tree spread the disease into my landscape? The short answer is “it could.” However, if handled properly, the wood chips can be safely used in the landscape. If it is known that the wood chips are from a diseased tree, allow them time to dry out completely before spreading in the landscape. To be safe, avoid spreading the mulch around trees of the same species where the wood chips originated.
Will using wood chips near my home encourage termites? This can be a concern if the wood chips are mulched right up to the foundation of the house. Termites are light and heat sensitive and will not bother the chips themselves if they are 3 inches deep or less. Therefore, keep the depth of the mulch less than three-inches near the house and other buildings. Also, leave a bare area several inches wide next to the house so that any termite activity is noticeable. (Cynthia Domenghini)
Contributors:
Cynthia Domenghini, Instructor
Ward Upham, Extension Associate
Division of Horticulture
1712 Claflin, 2021 Throckmorton
Manhattan, KS 66506
(785) 532-6173
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Cooperating, Ernie Minton, Dean.
