Q: As a gardener of fruits and vegetables, I want to know how I can get the most bang for my bucket of water. Which of the commonly grown spring/summer plants – such as tomatoes, zucchini, beans – yields the most produce per volume of water? If you had limited water to use on a garden of edibles, what would you select to grow this summer of drought? – Melanie Loo, Sacramento
A: Grow beans. They have built-in drought resistance.
In fact, several summer favorites do pretty well with restricted water. Beans native to the Southwest or other areas with hot summers and little rain can do well this summer in Sacramento. Tepary beans, for example, thrive in the Arizona desert.
Black-eyed peas need hot temperatures to produce good crops and like less water, not more. Lima beans can get by on limited water, too. Snap beans and pole beans need only short growing seasons and will set crops with little water.
Tomatoes, melons and squash grow deep roots that seek out water. Those deep roots benefit from weekly deep irrigation. Dark Star, a variety of zucchini, is especially adept at producing a large crop with limited water.
Several melon varieties are recommended for hot, dry summers: Missouri Gold; Top Mark; Sweet Passion; Kansas; Edisto 47; Crimson Sweet watermelon; and Strawberry watermelon. Those are all heat- and drought-tolerant varieties suggested by Southern Exposure Seed Exchange.
Sacramento radio host Farmer Fred Hoffman recently compiled a list of drought-tolerant crops for Sacramento home gardeners. Besides all those melons and beans, he included okra (Gold Coast, Stewart Zeebest, Beck’s Big Buck); eggplant (Listada de Gandia, Black Beauty, Ping Tung Long); peppers (Carolina Wonder, Charleston Belle, Aji Dulce); cucumbers (Little Leaf H-19, Ashley, Suyo Long); squash (Moschata, Tromboncino, Waltham Butternut); and pumpkin (Seminole).
If trying to decide between two varieties, look at their leaves. Vegetable plants with smaller leaves tend to lose less moisture due to transpiration. Veggies with big floppy leaves will suffer more in drought conditions.
Among the tomatoes, the varieties that tend to be drought stars include: Cherokee Purple; Mortgage Lifter; Legend; San Marzano; Arkansas Traveler; Red Star; Tropic; Ozark Pink; Valencia; and Neptune. But most tomatoes will do OK even on a water diet.
Mature tomato plants need about 1 gallon a day; that comes out to just under 1 inch of irrigation a week. That’s less than lawn. That doesn’t mean water the tomatoes every day; split their water ration to two or three times a week. If they’re drooping in triple-digit weather, give them a drink.
To help tomatoes make the most of what moisture they get, give them a double layer of mulch. Spread newspaper (such as the print edition of The Sacramento Bee) six to eight pages thick around the tomato plants. Then, cover the newspaper with two inches of organic mulch (such as compost, dried leaves or shredded bark). That helps the soil retain that precious moisture.
As for what not to plant: Skip the corn; it’s a major water hog and does not form ears well when irrigation is cut back.
Shallow-rooted lettuce is not drought tolerant (and usually struggles during Sacramento summers anyway), so cut back on summer greens – or grow them in pots on a patio with dabbled sun where they can get some shade (and attention if they wilt).