Some top trees and shrubs for summer color include crape myrtle (Lagerstroemia), desert willow (Chilopsis linearis), yellow bird of paradise (Caesalpinia gilliesii), butterfly bush (Buddleja), and rose of Sharon (Hibiscus syriacus).
Aster, hyssop, purple coneflower, Russian sage, scabiosa, thyme, and yarrow are also good bets.
Give flowering container gardens a bloom booster fertilizer every 10 to 14 days to trigger heavy flowering. A mid-month feeding will spur roses to flower one more time before frost arrives.
Keep deadheading. For the most flowers and tidiest garden, deadhead daily. Some gardeners take a few minutes each morning, making it part of their daily routine.
Keep adding mulch to areas of the garden that dry quickly. Mulch helps reduce soil temperature, cooling plant roots. Mulch also slows water evaporation from soil, keeping plant roots moist.
For established trees and shrubs in soil that you have amended with organic matter, adjust watering schedules as temperatures rise.
Water every 10 to 14 days, soaking soil roughly 3 feet deep.
For more efficient irrigation, place a soaker hose at the dripline of plants.
Through mid-month, continue to pinch back garden mums and other perennials that bloom late into autumn. Pinching them keeps them compact.
Prune all spring-flowering shrubs by early this month. Later pruning could reduce next spring's flower show.
Harvest onions when tops bend over. Harvest garlic when a few of the outer leaves are brown.
Dig bulbs carefully and dry them in a shady spot a few days. After drying, snip roots and tops. Store bulbs in a cool, dry pantry. To create onion and garlic ristras, don't cut tops -- instead, it's best to braid them.
You can speed up fig ripening using an ancient practice known as oleification. You'll need a cotton swab and olive oil, and you'll also need to check the pulp on the oldest fig on the plant. (Older figs are lowest on the branches.)
Cut open the oldest fig to see if the pulp is pink. If it is, dip the swab in olive oil. Apply a dab of oil on the eye at the bottom of each remaining fig. Treated figs will ripen in about a week.
At lower elevations, prickly pears will ripen late this month. Ripe fruits are a bright magenta hue. For safest harvest, use steel tongs to remove fruits from the cactus.
Spring-planted lettuce, spinach, and other greens will be preparing to bolt (flower), if they haven't already. Pull plants and throw them on your compost pile and turn soil so it's ready for August planting of fall salad crops and vegetables.
A blast of water is also a good solution for cochineal scale, which resembles white bits of duff. It's especially common on purple prickly pear pads this time of year.
Lightweight horticultural oil, sometimes called summer oil, controls garden pests, like aphids, mites, scales, and mealybugs. When using, be sure to coat leaf undersides thoroughly. Before applying, it¿s best to water plants thoroughly.