Gardening This Weekend: August 7, 2025
Things are warming back up. I don’t need to remind you – early morning and late evening are the best times to be gardening in Texas in August. Even then, though, wear a big hat and sunscreen.
PLANT
• Fall zinnias, marigolds and celosias. Buy potted transplants that are in bud but not yet in bloom whenever possible. Finish these plantings up soon in North Texas, by mid- to late August in South Texas.
• Finish planting beans, cucumbers and squash. North Texas gardeners: start looking for cabbage, broccoli, Brussels sprouts and cauliflower transplants.
• Dig and divide crowded daffodils, jonquils and narcissus before new root growth begins. Start looking at better bulb catalogs in-hand and on-line now to ready your orders for new types you want to try. Place your order within the next several weeks to have the best selection.
• Plant fall crocus, spider lilies, surprise lilies and oxblood lilies as you find them in garden centers.
PRUNE
• Any leftover freeze or wind damage to trees and shrubs. Trim erratic growth from shrubs, but whenever possible avoid formal shearing into globes or cubes.
• Remove flowers from coleus, basil, mint, lamb’s ear, caladiums and other plants where flower buds and flowers stop production of new foliage.
• Rose bushes by one-third to reshape the plants and increase vigor for fall bloom. Each cut should be made just above a bud that faces out from the center of the plant. Check, too, to be sure your roses don’t have the fatal rose rosette virus. Infected plants must be removed immediately, roots and all. I have much more information on my website.
FERTILIZE
• Bermuda turf with all-nitrogen lawn food in which half or more of the nitrogen is in slow-release form. Do not fertilize St. Augustine for another 3-4 weeks to avoid late-season outbreak of gray leaf spot (fungus that is exacerbated by applications of nitrogen).
• Patio pots and hanging baskets with water-soluble plant food every couple of times that you water them. Nutrients leach out of their porous potting soils quickly.
• Iron/sulfur additive to correct iron chlorosis in iron-deficient plants. Look for yellowed leaves with dark green veins, most prominent on newest growth first. Function of the sulfur is to acidify the soil so that the iron will remain soluble as long as possible.
ON THE LOOKOUT
• Seeing chewed leaves on plants? Look for damage and droppings on new growth. If you don’t see any, they may have moved on. If you think they’re still active apply Bacillus thuringiensis for caterpillars and many other pests. Sevin dust is effective on many chewing pests as well.
• If your crape myrtles have sticky, glossy leaves they have been visited by either crape myrtle aphids or crape myrtle bark scale. Spray with Imidacloprid for both (although using it as a soil drench in mid-May is more effective on the scale insects). Black sooty mold will grow in the sticky honeydew residue. You may be able to rinse that off with dishwashing detergent sprayed onto the plants under fairly high pressure and scrubbed off the trunks with sponges, but the better long-term solution is to prevent the insects that leave the honeydew behind.
• If you have browned, dry, and dying spots in St. Augustine, that’s probably chinch bugs. Look at the interface of the dead and healthy grass. You’ll probably find small black insects flitting around there on top of the soil. Look for irregular white diamonds on their backs. Treat with a labeled lawn insecticide.
• There is a great deal of lacebug damage to leaves of lantanas, azaleas, pyracanthas, Boston ivy, sycamores, chinquapin oaks, bur oaks, lacebark elms, American elms, and several other common landscaping plants. Leaves will turn tan on their topsides and black, waxy specks will be evident on the backs of the leaves. Afflicted leaves won’t green back up again, but you can stop further damage with almost any general-purpose insecticide.