Summer lawn care tips

July continues to be a busy time for gardeners. Consider the following reminders to help your lawn to be the envy of the neighborhood. 

Frequent mowing during periods of active growth makes for easier mowing. Generally, no more than one-third of the total grass blade length should be removed at any single mowing. If more than this is removed, the grass may become weak and stunted, especially during times of drought. In other words, try not to scalp your lawn!

Grass kept at the proper height will help keep the soil shaded and relatively cool and tends to discourage weed growth. If weed seeds do germinate, the relatively tall, vigorous grass will tend to smother the weed seedlings. 

Clippings more than an inch long are likely to remain on top of the grass until they turn brown. Since they detract from the uniform appearance of the lawn, they should be raked up and removed. Clippings shorter than one inch will sift through the grass and decompose rapidly and will not contribute to thatch buildup.

Your lawn may be suffering from a nematode infestation. Nematodes are microscopic worms that live in the soil and feed on plant roots, weakening the host plant. Symptoms include off-colored, yellow, stunted blades of grass. The grass may appear to be suffering from lack of fertilizer or water but will not respond to applications of either. Nematodes are particularly troublesome in light, sandy to sandy loam soils.

Carefully examine the roots of the grass for signs of abnormal growth. Affected roots will appear shriveled, blackened, and stubby. Fewer small, white feeder roots will be observable. If nematodes are suspected, it is best to contact your county extension service for positive identification and proper methods of control. 

Is your centipede declining? If your centipede lawn has failed to green up properly, it could be that the lawn is suffering from centipede decline. Factors thought to contribute to this problem include high phosphorus levels, too low or too high pH, high nitrogen applications, heavy thatch buildup, compacted sod, winterkill, insect damage, and mowing too high. These factors may act independently or in concert with other factors to cause the problem. 

Try this for small, workable areas: remove any thatch in the dead areas and till the soil to a depth of about six inches. Then resod or seed at the recommended rate and keep watered to establish the grass. Withhold any fertilizer or lime applications from the newly established grass unless a soil test indicates otherwise. Maintain a proper mowing height and remove all clippings from the area.

Insect damage to lawns is not easy to determine. One way to check if you have harmful insects is to “float” them out. Mix two ounces of lemon-scented dish detergent in two gallons of water. Pour this solution over a two-foot by two-foot area. Insects such as sod webworms and chinch bugs will come wriggling to the surface. Collect the insects and have them identified by your local Extension Service or lawn care professional.

Even on a well-established lawn, mowing in the same pattern over and over will result in compaction where the wheels roll. It is wise to use a different mowing pattern (vertical, horizontal, or diagonal) each time you mow. 

Turfgrasses have varying degrees of drought tolerance. Ranked from highest drought tolerance to lowest:

First: Bermuda 

Second: St. Augustine

Third: Centipede, Fescue, Zoysia

Fertilizing the lawn is an important step for ensuring an attractive landscape: 

Bermuda: fertilize now (and again in August and September)

St. Augustine: fertilize now

Zoysia: do not fertilize now unless a previous feeding was missed

Fescue: to avoid disease and drought related problems, do not fertilize fescue during the summer

I hope these pointers will help you in maintaining your lawns.

Tim Lewis is a Georgia Green Industry Association Certified Plant Professional, gardening writer, and former Perry High School horticulture instructor. He can be reached at (478)954-1507 or timlewis1@windstream.net.