Install a rain barrel

Rain barrels typically hold about 50 to 60 gallons each―enough to irrigate houseplants or pots on the deck. The best type is made of recycled food-grade plastic (or use a recycled wine barrel like the one pictured), with an intake line, spigot, overflow attachment, screen cover to keep out leaves, and removable solid cover.

Position the barrel beneath a downspout; to keep the rainwater pure, remove the solid cover an hour or two after rainfall has washed pollen and other pollutants off the roof.

Rain barrels cost about $100 to $150 each.