Care for Late-Season Perennials
Late-summer and fall-blooming perennials like Mexican bush sage, Mexican mint marigold, copper canyon daisy, and fall aster should not be sheared after mid July to give them time to grow and set bloom buds on the ends of the new growth. Give them a little boost of fertilizer and keep the soil moist to maintain good health and vigor.
Plant Fall Vegetables
Late July and August is the time to get in that final planting of warm-season veggies, such as summer squash, cucumbers, green beans, chard, and even okra ... but hurry! Potatoes should be planted in mid to late August. Start them in 4-inch pots in a bright shady area and then transplant them into the garden in mid to late August. This decreases losses from rot in the hot summer soil. Planting whole smaller potatoes also helps reduce losses from decay.
Rejuvenate Summer-Blooming Shrubs
To keep chaste tree (Vitex), butterfly bush (Buddleia) and crape myrtle (Lagerstroemia) blooming well, trim back spent blooms to prevent the plant from expending energy on seed production. The first two shrubs can get rather loose and unattractive following a good bloom cycle. Trim them back by a third and then provide a little water and fertilizer to stimulate regrowth and another attractive bloom cycle
Water Next Year's Fruit Now
Most deciduous fruit trees, vines, and bushes are setting fruit buds in mid to late summer for next year's crop. If trees are stressed by drought now, next year's production will be affected. In addition, drought-stressed peaches also will tend to set more "doubles," twin fruits that won't develop normally. Persimmons will drop fruit if they encounter soil moisture stress. Remove vigorous upright shoots emerging from the scaffold limbs and from the base of the trunk to prevent them from shading out the interior portions of the tree.
Pamper New Seeds
To get seeds up and going in this heat, give the seed furrow a deep soaking prior to planting. This "preplant" irrigation is important. Then water the seeds in well after planting. Place a little shade cloth or row cover over the row to slow drying of the soil and reduce soil temperature.