9. Deep-root irrigators. These hose-end devices have forked or needlelike shafts that inject water into the ground. You insert the shaft 6 to 12 inches or deeper into the soil around trees and shrubs. After watering in one spot along the drip line, you move the irrigator to another spot until you complete one round trip. For a tree with a 12-inch-diameter trunk, which needs 60 minutes of water (flowing at 2 gallons per minute), you would insert the irrigator at six points around the drip line, letting it run 10 minutes at each point. The needle-type Root Irrigator ($25, plus shipping) is sold by Gardener's Supply (see tactic 8).
10. Be water-wise with containers. Use glazed terra-cotta or plastic ones, which hold water better. For extra insulation, nest smaller pots inside larger ones, or bury pots in the ground up to the rims.