We turned the corner from pleasant spring weather into the precursors of summer at a high rate of speed. Boom! It was hot, and now we're staring down the barrel of 12 or 15 more weeks of what we see out there right now. We don't like it a bit -- and neither do our plants. Let's outline the basic steps to survival.
Choose your new plants carefully. Choose only types that can handle the heat. Crape myrtles and palms are classic examples of larger plants that are easily started right now. Tropical annuals such as hibiscus, mandevilla, brugmansias esperanza and crotons are, too. You can also plant trailing lantanas, purple fountaingrass, purslane, moss rose, firebush, pentas, angelonias, gomphrenas, copper plants and firebush.
Plants will really begin to show moisture stress after a couple of weeks of hot weather. Large-leafed, fast-growing shade trees will begin to lose older leaves that were produced in the cool, moist weather of early spring. Don't be at all surprised if you see yellowed leaves beneath fruitless mulberries, cottonwoods, silver maples, catalpas and other fast-growing species. All you can do is to keep these trees watered properly. They'll come out of it just fine, but they'll shed a good many leaves in the process. It happens every summer.
Water and mulch
Water deeply (to encourage deep root growth), then wait until the top of the soil begins to dry before you water again. Use soaker hoses, hose-end sprinklers and water breakers to spot-water between general irrigations. New plants are especially vulnerable, since they don't yet have well-developed root systems. While you normally don't want to put watering on a regular interval, in the case of these new plants, you'll probably want to soak them every two or three days just to be sure. Monitor your sprinkler heads to be sure they're working properly. This is also a good time to have a "smart" controller installed to monitor your soil, sites and plants, as well as the local weather, to determine when the system needs to run, and for how long. It's a money-saving and water-conserving use of technology.
Mulch heavily, and remove competing weeds. Apply 1 to 2 inches of compost, shredded pine bark, cypress or hardwood mulch. The choice is pretty much up to you. The mulch will lessen soil-to-air contact, so that the soil won't dry as quickly. It helps rainfall and irrigation soak into the soil more efficiently. It moderates the rate at which the soil changes temperature, and it will certainly suppress the development of weeds. That's a good thing, too, because weeds often use more water than the desirable plants.
Mow regularly, and at the recommended height. Many gardeners have the mistaken idea that letting the grass grow tall aids in its summer durability, but they fail to remember that tall grass becomes thin grass that's less able to ward off the weeds. The one exception to that mowing height comment might be for bermuda turf that looks scalped each time that you mow it. If you're mowing on 5-day intervals and if it's still browning because you're mowing into stem stubble, raise your mower one notch for the balance of the season. Remember to drop it back down again late next winter.
Fertilize with slow-release nitrogen for sustained feeding. It's time for the second feeding of your lawn grass and landscape plants. By using a quality fertilizer (half or more of its nitrogen in slow-release form), you'll be providing enough nutrients for the plants to thrive through the summer and until the early fall feeding.
Because they're in lightweight potting soils, and because we water them so often, container plants will need to be fed much more often. If you're using a water-soluble plant food, apply a diluted solution each time that you water. It's also good to add a timed-release, encapsulated fertilizer for sustained feeding.
Watch for pest problems that show up as plants are put under stress. Let your local retail nurseryman suggest the best controls for each pest. Use a long-handled pole pruner to remove webworms from pecans, walnuts and other trees. Bagworms are active on junipers, cypress and other conifers. Lace bugs will turn leaves of pyracanthas, azaleas, Boston ivy, boxwood and occasionally oaks a mottled tan color. Look for black, waxy specks on the backs of their leaves. Spider mites are causing similar tan mottling to marigolds, beans and especially tomatoes, among many other types of plants. Chinch bugs will cause dried patches of St. Augustine, particularly in the hottest and sunniest parts of your lawn. If you part the grass some hot afternoon, you should be able to see them in the area of the runners. They're BB-size and black, with irregular white diamonds on their backs.
St. Augustine may develop gray leaf spot issues in the hot summer weather. If areas appear yellowed, and if you see diamond-shaped gray/brown lesions on the blades and runners, apply a labeled fungicide and discontinue additional applications of nitrogen until it is cooler in early September.
Summer can be a rewarding gardening time, but as with most rewards, it comes with its challenges. Hopefully you're up to the match.
Neil Sperry publishes Gardens magazine and hosts Texas Gardening noon-1 p.m. Saturdays and 9 a.m.-noon Sundays on WBAP AM/FM. Reach him during those hours at 800-288-9227 or 214-787-1820.