Aphids, borers, caterpillars, green fruit beetles, grubs, whiteflies, spider mites (to name only a few) are active and in need of control this month. Before grabbing a broad-spectrum insecticide, identify which insects are causing the problem and research the best options, preferably ones that won’t kill beneficial insects, such as honeybees. Nematodes are especially active in warm soils. If you planted marigolds early in the season, you’ll be pleased to know they attract root knot nematodes and kill them with a natural chemical they produce. (Nematodes also do not like a humus-rich soil.)
The heat and dry air have caused a true decline in the garden. Even heat tolerant plants are wilting by noon. If they are not receiving regular irrigation, they will be lost. Containers may need to be watered at least twice a day. Always water deeply but allow the surface to dry out between waterings. In fire season, consider replacing flammable mulches with stone products. Keep the area around your home well irrigated and pruned.
Vegetables / Fruits
• Jobs in the vegetable garden this month include watering, harvesting, weed and pest control.
• Keep everything picked clean to keep the plants productive. Can, freeze or dehydrate the produce for winter use.
• Start seeds for cool season crops this month. Celery and all members of the cabbage family will be ready to go into the garden by the end of September.
• Do not feed your deciduous fruit trees in August, or they won’t achieve dormancy before cold weather.
• Mature fruit trees in the interior valleys need two or three deep waterings a month during the growing season if there’s no rain. Along the coast, once or twice a month should be plenty.
• Pick corn when the silks are crisp and brown and the kernels have a milky juice in them.
• As you continue to fertilize roses, scratch the nutrients lightly into the soil. Continue treating for pests and disease.
• Cut back roses lightly during the final week of August to promote a great fall bloom. Remove suckers sprouting below the bud union.
• Cut to the ground stems of daylilies and agapanthus that have finished blooming.
• Plant Meyer hybrid alstroemerias (Peruvian lillies) for fall. They are easy to grow, less invasive than other types, and more heat tolerant.
• Fertilize biennials such as dianthus with fish emulsion at weekly intervals this month.
Trees / Shrubs
• Fire resistant trees are those less flammable than cedars, eucalyptus, palms and pines. They include: Chinese banyan, crape myrtle, ginkgo, jacaranda, live oak, and sweet gum, to name a few. If you plan on adding trees this fall, order now.
• Remove low-hanging branches of mature trees so the canopies are high off the ground in case of fire. Always keep branches at least 10 feet from the roof and wooden decks on your house.
• Young trees and trees growing in sandy soil need frequent watering this month.
• Water sprouts are straight, whip-like shoots that grow from the base of the trunk and vertically from branches in the centers of mature fruit trees. As soon as you see this growth, cut it flush to the tree. If not removed, it will compromise the strength of the tree.
• Warm-season grasses look their best this month (Bermuda, St .Augustine, zoysia). Cool season grasses look their worst (fescue, annual rye grass, Kentucky bluegrass).
• Water warm season grasses deeply and infrequently, feeding every four to six weeks. Let cool season grasses go dormant. Follow the manufacturer’s directions when fertilizing. Overfeeding will stress the turf.