(Backyard Gardener - Photo Illustration - MetroCreativeConnection)

Hello Mid-Ohio Valley Farmers and Gardeners! Beautiful sunshine and mild temperatures have dominated the weather this week. This week I want to talk about summertime lawn care.

I know summer does not officially start until June 21, but our weather patterns can change from week to week. Now is the ideal time to plan ahead for the hotter, dryer conditions of summer, which I believe are on schedule to arrive next week with temperatures in the upper 90’s. This combination of hot and dry can be harmful for the turf. Now is the time to take proactive steps to help the lawn survive summer’s onslaught.

First, let’s take a look at mowing height. I recommend setting the mower deck at 3-4 inches. This will shade out weeds, reduce water loss to evaporation and assist in building a stronger root system that is more tolerant to drought. I guarantee you will have a healthier, more attractive looking lawn.

Mowing higher reduces the amount of water used by the plant, and the grass stays green longer. A higher mowing deck height is very beneficial to cool season grasses such as bluegrass and tall fescue during extremely hot and dry periods in summer.

Longer leaf blades provide a shading of the soil to reduce the soil temperature and moisture loss. These conditions favor root growth which is vital for increased summer tolerances.

In addition to the proper mowing height, make sure your mower blades are sharp. A dull blade rips the grass blade resulting in increased moisture loss and excess browning to the grass leaf. The jagged edges from dull cuts also make plants more susceptible to diseases.

Cleanly-cut grass blades are able to conserve water, reducing the need for irrigation. A dull cut often leaves the grass with a whitish appearance to the lawn. A sharp mower blade cuts easier and produces less engine drag, which means your grass is quicker to cut and your lawn mower will last longer. Dull mower blades also tend to increase the likelihood of rigid cuts and uneven grass length.

Sharpen or replace the lawn mower blade on a regular basis as a part of regular overall turf and mower maintenance. It is handy to have some spare sets of blades, and you can sharpen them yourself or take them to a local shop.

I recommend leaving clippings on the lawn for healthier grass. Clippings break down quickly and encourage beneficial microorganisms and earthworms. Nutrients in the clippings are recycled into the lawn, promoting steady grass growth. Clippings left on the lawn also means no bagging and hauling, saving both human and fuel energy.

Clippings contain nitrogen and other nutrients. When returned to the lawn, clippings recycle nutrients in an organic, slow-release form that promotes steady grass growth. Returning clippings reduces the amount of supplemental nitrogen fertilizer needed by lawns.

The idea that clippings left on lawns will cause thatch has been disproven. Regular core cultivation (aeration) is the best way to prevent thatch.

Core cultivation or aeration is another important lawn maintenance practice. It opens up airways and relieves soil compaction. It can be done as often as needed, as long as the root systems are actively growing. For homeowners, an economical way to do this is to rent an aerator with a neighbor.

Soil compaction can be a problem in clay soils, which aeration helps alleviate. A compacted soil means that the soil spaces underground that allow water, nutrients and air to move freely are limited. To get healthy, thick turf grass on top of the soil, the grass needs healthy well-developed root systems under the soil.

Dry conditions in summer are not ideal for fertilizing cool season grasses. Avoid applying excess nitrogen fertilizer during hot, dry conditions. Lawn grasses will respond by putting out excessive growth when they should be going dormant. Drought stress will occur faster on turf stands with poor soil conditions underneath. Soil compaction, clay fill, low pH, and general poor conditions for root growth will become very evident under stress conditions such as drought.

The best time to fertilize bluegrass and tall fescue is in the fall months, September and November. In fact, spring applications should be avoided unless the lawn will be well watered during the summer months. Spring fertilization provides little benefit to the grass plant except to make the grass green, often resulting in lush growth. This lush growth increases mowing requirements.

Under regular summer watering schedules an application of slow release fertilizer applied in mid-May is acceptable.

It is almost inevitable we will have a summer dry spell here in the Mid-Ohio Valley. During a dry spell, many lawns will show initial symptoms of drought stress. As the grass loses water, its leaves become less rigid and begins to wilt. You can see footprints remaining after walking across the lawn because the grass stays flat after it is stepped on rather than “bouncing back.”

The most obvious symptom of drought stress is crunchy tan or brown leaves of grass that have entered dormancy. This helps the plant conserve water to stay alive and survive a drought. Drought stress is most noticeable on slopes in the lawn established on poor soil or shallow topsoil.

Once cool-season turf grasses have gone dormant by stopping active growth and turning off-color it’s best to leave them in that condition rather than watering heavily to cause the

grass to green-up again. Breaking dormancy actually drains root reserves within the plant, and if conditions remain dry and the weather is hot, the plant is not likely to replace those reserves. In a normal summer, lawns may go dormant and resume active growth when conditions improve. The downside of dormancy is the appearance of the lawn and the risk of problems arising on an inactive lawn such as opportunistic weeds sprouting.

Many homeowners want to know how much water is enough to keep the turf alive. In order to keep your lawn green during hot and dry periods, at least one inch of water will need to be applied weekly. That can be expensive as well as using quite a bit of water for an extended dry period.

The best way to care for your lawn is by following recommended practices determined by university research. Contact me at the Wood County WVU Extension Office 304-424-1960 or e-mail me at jj.barrett@mail.wvu.edu with questions. Good Luck and Happy Gardening!

***

Question of the Week: What are insecticidal soaps and how do I use them?

Insecticidal soaps are applied as a foliar application (sprayed on plant leaves) and are effective on a wide range of plant pests when the soap spray comes into contact with the pest.

Most commercially available insecticidal soaps are made of potassium salts of fatty acids and kill by disrupting the structure and permeability of insect cell membranes. Insecticidal soaps are most effective on soft-bodied insects such as aphids, adelgids, lace bugs, leafhoppers, mealybugs, thrips, sawfly larvae, spider mites and whiteflies.

They are not effective on pests as a residue on the plant surface, and therefore are not toxic to pollinators after the spray dries. They can be safely used at any time to control pests on plants that are not attractive to pollinators. However, on pollinator-attractive plants, spray at dawn or dusk when pollinators are not present.

Generally, concentrations of insecticidal soaps exceeding 3% may cause some leaf or flower injury, and concentrations as low as 1.5% may injure sensitive plants. Read the product label for a list of sensitive plants and avoid spraying those. If you are uncertain of a plant’s sensitivity, spray a few leaves or flowers first and wait at least three days to watch for symptoms of spray injury, which include yellow, black or brown spots, brown (necrotic) edges on leaf and petal tips, scorch or discoloration.

Some landscape plants known to be sensitive to insecticidal soap are horse chestnut, mountain ash, Japanese maple, sweet gum, jade plant, lantana, gardenia, bleeding heart, sweetpeas, crown-of-thorns and some cultivars of azaleas, begonias, chrysanthemum, fuchsias and impatiens.

It is best to purchase a commercial product formulated for use on plants rather than prepare your own spray from dish-washing detergents or other household cleaners because homemade recipes may be more toxic to plants. Most such products are detergents rather than true soaps, which can damage your plants. Only use products that are

specifically formulated and labeled for use as insecticide. Many insecticidal soap products are listed by the Organic Materials Review Institute (OMRI) at www.omri.org.