Gardening This Weekend: June 17, 2021

As we head into the prime part of the summertime, here are the critical objectives for the next several days.

PLANT
• Hot-weather annuals to provide color now until frost. Your Texas Certified Nursery Professional can guide you to the best choices, both in annual flowers and foliage and in tropical plants.
• New turf from sod, plugs or seed. You’ll have to water at least daily, perhaps morning and evening, for the first couple of weeks to help the grass get established.
• Crape myrtles while nurseries have their best supplies of the year. Plants are in bloom now so you can match your chosen colors. Look carefully at each type’s mature size to be sure all will fit the spaces you have for them.

PRUNE
• Do not prune oaks yet if you’re considering reshaping or removing them due to winter damage. Give them more time. Some are still pushing out new growth and foresters and arborists tell us not to hurry.
• Conversely, ash species that were hurt by the cold and dead top growth in crape myrtles can be removed.
• Spring- and early summer-flowering perennials to remove spent flower and seed stalks.
• Leggy annuals, including begonias, coleus, copper plants and others to keep plants more compact.

FERTILIZE
• Bermuda lawns with all-nitrogen fertilizer (half or more of that nitrogen in slow-release form). Do not feed St. Augustine or zoysia lawns during heat of summer if gray leaf spot fungus has been a problem in years past.
• High-phosphate, liquid root-stimulator fertilizer monthly to newly planted balled-and-burlapped trees and shrubs for first year in landscape.
• Iron with sulfur additive to correct iron deficiency (yellowed leaves with dark green veins most visible on newest growth at tips of twigs). Keep iron products off brick, mortar, stone and concrete due to staining.
• Patio pots and hanging baskets with water-soluble, high-nitrogen food with each watering.

ON THE LOOKOUT
• As summer hits full stride, chinch bugs will return to hottest, sunniest areas of St. Augustine. Grass will appear dry but will not respond to irrigation. The bugs themselves will be visible in dying areas (not in dead grass). They are BB-sized, black with white diamonds on their wings. Apply labeled insecticide as soon as you identify them. They can kill large patches within a few days.
• Gray leaf spot will cause St. Augustine and zoysia lawns to turn yellow. On closer inspection you’ll see BB-sized grayish-brown lesions on the blades. Apply Azoxystrobin fungicide (sold as Scott’s Disease EX) to stop its spread, but also discontinue any applications of nitrogen until fall.
• Webworms will soon be forming webs in pecans, persimmons, walnuts and other trees as larvae feed on foliage. It may be easiest to prune out small webs as they develop. Use long-handled pole pruner, and be very mindful of any power lines that might be nearby. Or you could spray with a labeled organic or inorganic insecticide if the webs aren’t too high in the air. Include one drop of liquid dishwashing detergent with the spray to help it break the surface tension of the webs so spray can penetrate.
• Spider mites attack tomatoes, marigolds and a large percentage of our landscape and garden plants. They produce fine tan mottling. Thump a suspect leaf over white paper. The mites will be very tiny, and if present they will start moving across the paper. Several insecticides are labeled for control of spider mites, although you’ll often need to repeat a couple of times. Be sure sprays coat the lower sides of leaves as well as the tops.
• Lacebugs will begin to attack blades of American elm, sycamore, bur oak, azalea, pyracantha, boxwood, Boston ivy and other plants, turning them mottled tan. You will see black peppery specks (excrement) on backs of leaves. Apply general-purpose insecticide at first evidence to stop further damage. Systemic insecticides work well, but they may take 10-14 days to have good effects.
• Leafrollers will attack foliage of redbuds, sweetgums, trailing periwinkle groundcover, cannas and other ornamental plants. Apply systemic insecticide spray as soon as you see them for control. You may even want to apply preemptively.