Summer is arriving a little late this year. Comparatively cool weather in May and wet weather in June into early July delayed the inevitable: a hot, dry spell called “summertime in Texas,” but that’s exactly what we will have for the next several weeks.
Let’s take a look at this turn of events and how best we can cope.
Last good time to start new turf
Your cutoff date for starting new lawngrass is the middle of September. After that, there’s too much risk that the first freeze of winter will catch it before it has a chance to get rooted in really well. But if you plant now in mid-July you should still be in good shape. That goes for seed, sod and plugs.
Get rid of the existing vegetation, especially weeds, before you start planting new grass. Chief among those are dallisgrass and nutsedge.
They’re difficult to eliminate from existing turf, so it’s best to have them out of the way before you ever start planting new lawns. Use a glyphosate product (no other active ingredient) to kill dallisgrass without leaving any residue in the soil to harm your new turf.
Allow 10 to 12 days for it to do its job before you start working the soil. Use Image or Sedgehammer for nutsedge. Their waiting period is longer — upwards of 30 days.
The only down side of planting new grass right now is that you’ll have to be ultra-attentive to its water needs. New grass roots are quite near the soil’s surface, and that means that they can dry out in only a few hours.
Water lightly morning and evening for the first couple of weeks, then gradually cut back to once daily, then every couple of days as you wean the grass off the frequent waterings.
Mowing heights and patterns
There is considerable discussion about heat and drought tolerance and whether raising the mowing height helps with those at all.
My feeling is that it does not. As grass is cut higher it becomes thinner and thinner. That allows sunlight to hit the ground directly, drying the soil out more rapidly. Mowing at the recommended height, by comparison, keeps the grass low and dense.
If you are finding that bermuda turf is browned for a day or two after each mowing, and if you’re sure that your blade has been properly sharpened fairly recently, you might want to try changing your mowing pattern.
Most of us mow in large squares or rectangles, but when we mow at 45-degree angles it’s amazing how good the lawn can look as the grass loses its pattern or “grain.”
Try mowing on shorter intervals, too. If it’s been on 7-day turnarounds, mow every 5 or 6 days for a few weeks to see if that helps
It may be that you’ve been letting the grass grow too tall between mowings. That can result in your removing excesses of blade tissue. It takes the grass a couple of days to recover each time that you mow.
Insects and diseases
Chinch bugs attack St. Augustine in the hottest, sunniest parts of the lawn. The grass looks dry, but irrigation doesn’t help it rebound.
If you part the grass with your fingers you’ll see the small black insects with irregular white diamonds on their backs. They’ll congregate near the boundaries of healthy and dying grass. Your local nurseryman can show you several products labeled for the control of these damaging pests.
Note, too, where they show up. It’s quite common for them to return to the very same spots year after year.
Gray leaf spot is another problem for summer St. Augustine. The turf appears yellow in uneven washes, both in sun and in shade. Your first inclination will be to reach for the bag of nitrogen fertilizer, but in reality that’s the worst thing you can do. Nitrogen exacerbates this fungus.
You can confirm its identification by looking at individual blades. It causes diamond-shaped gray/brown lesions a little larger than BBs, usually along the blades’ midribs and sometimes on the runners as well. Treatments for gray leaf spot: (1) discontinue all nitrogen applications to St. Augustine mid-June through early September and (2) apply a labeled turf fungicide.
There aren’t a lot of products at the retail level that consumers can buy. Have your local independent retail garden center manager show you what they have in stock.
Bermudagrass smut shows up in early to mid-summer each year. Flower heads turn greasy black, looking like they’ve been dusted with soot. It’s not especially harmful, unless you’re a pair of white sneakers. The best controls for bermudagrass smut would be to mow frequently so the grass doesn’t have time to produce its flower and seed heads, also to apply a high-nitrogen fertilizer to keep it vegetative.
Mushrooms continue to pop up across North Texas lawns. People become very concerned when they see 50 or 100 mushrooms appear overnight, but the fact is that they’re living off decaying organic matter like old tree roots, building debris and even grass clippings.
They pose no threat to your lawn grass, to the trees or to any of your other plants. They disappear almost as quickly as they show up.
Learn to enjoy them. There is no call to action.