August Gardening Guidelines
by Keith C. Hansen, Extension Horticulturist, Smith Co. – Tyler, Texas
August is here and gardening is far from the minds of most folks. An ice cold lemonade and deep shade to beat the heat is what most gardening calendars call for. However, fall is right around the corner and here are a few tips to get you through the scorching days of August and into the “second spring” of the south – fall.
August is typically one of the driest months of the year in East Texas. Even if does rain, chances are it isn’t enough to supply the needs of your lawn and garden. Use rain gauge to actually measure how much rain you’re receiving. Lawns and shrubs need about an inch of water per week in the summer time. Often the showers may seem like they are dumping a lot of water, but they may be too brief to penetrate the ground more than an inch. Make the best use of water by giving plants a thorough soaking as infrequently as the weather and your soils will allow.
Many plants will signal their need for water: turfgrass lies flat after being walked on, and many plants loose their shine and droop a little. Unfortunately, most trees do not readily show drought stress, yet are negatively impacted by prolonged droughts, and the effects can carry over to the next few years. Weakened trees become more susceptible to other stresses and diseases, and may succumb after a series of droughts.
When watering lawns during hot weather, do it early in the morning. Otherwise, much of the water will evaporate from the grass before the plants get to use it. To further avoid excess evaporation, use a sprinkler that produces large drops of water instead of a fine mist.
Check the thickness of mulch around your shrubs, flowers and newly planted trees. Unmulched soils can reach more than 100 degrees, hot enough to kill roots. Mulched soils can be three to 10 degrees cooler even several inches deep. Besides reducing soil temperature, mulches also conserve water by reducing evaporation, often up to 65 percent. In one test, pine needles gave the greatest reduction in soil evaporation. Of course, mulch reduces weeds which also compete for water.
Here are some mulching materials and suggested depth for each: shredded bark (3-4″), wood chips (3-4″), bark chunks (4-6″), chipper debris (3-4″), sawdust, wood shavings (1-3″ – use only aged, weathered materia), pine needles (2-3″), lawn clippings (1″ – dry clippings before use), leaves and leaf mold (2-4″), partially decomposed compost (2-4″).
Chinch bugs are a major lawn pest of St. Augustine in the summer. If patches in the lawn look dry, like it needs water, and you are certain, after testing the soil, that is getting sufficient water, then suspect Chinch bugs. Be sure your sprinkler is doing a proper job. Low water pressure may result erratic coverage or “hot spots” in the yard that need supplemental water. Check with a shovel and your fingers to determine soil moisture levels.
August is also the month to begin checking for the presence of white grubworms. Not every lawn will need grub worm control. As a matter of fact, probably only a small portion of lawns are bothered by these pests. Lawns which have been heavily damaged in the past by these root-eating, soil-dwelling white grubs are prime targets to be attacked again. White grub damage is characterized by a very loosely rooted turf which can be very easily pulled up. If grubs are suspected, check the soil under affected grass for the small, white grubs. Now through mid-August is the time to apply insecticides to control white grubs if you find them. Be sure to thoroughly water the insecticide into the soil immediately after application.
Azalea lace bugs are a major pest of azaleas, and increase rapidly in the summer time. Affected azalea leaves look like they are stipples until they are almost white. A quick look on the underside of leaves will reveal black, varnish-like spots which is a sure sign of azalea lace bugs. Spray with an insecticide, making sure the spray contacts underneath the leaves where the lace bugs are feeding.
Use pesticides with caution and only as needed. Follow all label directions and never increase the rate. Do not rinse sprayers or dispose of excess spray in the drain, storm sewer or other place where runoff can contaminate our water system.
Starting in mid August plant broccoli plants, Brussel sprouts, cabbage plants, Chinese cabbage, carrots, cauliflower plants, Swiss chard, collards, kale, English peas, Irish potatoes, and summer squash.
Set out tomato transplants (if you can find them) right away for a fall harvest. Look for an early maturing variety (65 to 75 days). Remember that our average first freeze is mid-November and that tomato maturity slows down as the days get cool and cloudy.
Peppers and tomatoes planted earlier this year will not set fruit during the heat of summer, even though they may still be flowering. If the plants remain healthy, they will set fruit again once temperatures stay below 90 degrees. Sidedress established, healthy plants with fertilizer and keep watered to encourage new growth.
An eggplant is ready to harvest when the fruit is fully colored and has achieved the mature size for the variety. Seed should be white, and the tissue firm. If the seeds are brown and hard, or the skin has become dull rather than shiny, the fruit is past eating quality, so harvest the next fruit sooner.
Remove old plants that have stopped producing to eliminate shelters for insects and disease organisms.
ODDS AND ENDS
Order your spring-flowering bulbs now. A good guideline to use is ‘biggest is best’ in regard to bulb size. Be careful about so- called “bargain” bulbs as they may be small or of inferior quality.
Potted plants outdoors may need watering daily to prevent wilting. Such frequent watering will leach out nutrients, so be sure to regularly fertilize potted plants with a water-soluble fertilizer.
Finish planting lawns this month to give the new grass opportunity to become established before cold weather stops growth. Wait to fertilize established lawns until September.
A late-summer pruning of rosebushes can be beneficial. Prune out dead canes and any weak, brushy growth. Cut back tall, vigorous bushes to about 30 inches. After pruning, apply fertilizer, and water thoroughly. If a preventive disease-control program has been maintained, your rose bushes should be ready to provide an excellent crop of flowers this October.
It is not too late to set out another planting of many warm-season annuals, such as marigolds, zinnias, and periwinkles. They will require extra attention for the first few weeks, but should provide you with color during late September, October, and November.
Sow seeds of snapdragons, dianthus, pansies, calendulas, and other cool-season flowers in flats, or in well-prepared areas of the garden, for planting outside during mid-to-late fall.
Plant bluebonnet and other spring wildflowers. They must germinate in late summer or early fall, develop good root systems, and be ready to grow in spring when the weather warms. Plant seed in well-prepared soil, one-half inch deep, and water thoroughly.
Picking flowers frequently encourages most annuals and perennials to flower even more abundantly.
The information given herein is for educational purposes only. References to commercial products or trade names is made with the understanding that no discrimination is intended and no endorsement by Texas A&M AgriLife Extension Service personnel is implied.