By the end of August select potted plants of perennials such as autumn asters (Aster oblongifolius) or ornamental salvias for excellent fall color. These will become permanent occupants of the flower bed, capable of extended color for several years.
By August many fall vegetable seeds and even small plants may be set out for later production. Be careful to give extra water, and a little shade to these young plants while they are becoming established. The result will be excellent cool season garden produce.
Trim off faded flowers on crape myrtles to encourage later re-bloom.
Evaluate the volume of water delivered from lawn sprinklers to ensure healthy, stress-free grass during the heat of summer. One thorough watering that will deliver one inch of water at a time is better than several more shallow sessions. The amount of water available through flower bed sprinklers may be checked by placing several shallow pans among shrubs or flowers.
Caladiums require plenty of water at this time of year if they are to remain lush and active until fall. Fertilize with 21-0-0 at the rate of one-third to one-half pound per 100 square feet of bed area and water thoroughly.
Prune out dead or diseased wood from trees and shrubs. Hold off on major pruning from now until midwinter. Severe pruning at this time will only stimulate tender new growth prior to frost.
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.
It is time to divide spring-flowering perennials, such as iris, shasta daisy, oxeye, gaillardia, cannas, day lilies, violets, liriope and ajuga.
Make your selections and place orders for spring-flowering bulbs now so that they will arrive in time for planting in October and November.
Dont allow plants with green fruit or berries to suffer from lack of moisture.
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 fall.
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.
Establish a new compost pile to accommodate the fall leaf accumulation.
Gail Haynes is an Ellis County Master Gardener, a Texas Rainwater Harvesting Specialist and guest columnist in the Daily Light. For further information, contact the Ellis County Master Gardeners at the Texas AgriLife Extension Service, 701 South Interstate 35E, Suite 3, Waxahachie, or call 972-825-5175 or e-mail: email@example.com.