Cooks and gardeners love to argue about the difference between fruits and vegetables (all the trouble stems from differing definitions). But both sides get tongue-tied when it comes to rhubarb. Although it is a vegetable, its tart stalks are cooked, sugared, and used as a fruit. Rinse rhubarb, trim off leaves and dried ends, then cut stalks into pieces for cooking in pies, cobblers, and tarts. Enjoy it, but don't eat too much or you may be reminded of one of the plant's early medicinal uses: its roots were harvested as a powerful laxative. Rhubarb's poisonous leaves, of course, must be avoided; they are toxic if eaten. (Plant out of reach of children.)
WHERE IT GROWS: Best in zones 1 through 11 (in cold-winter areas it can produce for decades), but it can handle mild winters (zones 14?24) too, if summers aren't too hot. In the desert, grow rhubarb as a fall-planted annual for harvest in winter and spring; it stops growing and starts rotting when daytime temperatures average above 90°.
PLANTING AND CARE: Plant rhubarb with the top of the crown at the soil surface, and mulch with manure in fall and spring. Rhubarb is virtually pest-free, but it is vulnerable to drought. Cut out flower stalks when they appear.
HARVESTING: You can harvest in spring of the second year, but you won't get a full crop until the third or fourth spring. To harvest, pull stalks back from the base of the plant and twist. Don't cut them off ? the remaining stalk will rot. You can take up to a third of the stalks from a mature plant over a 10-week period every year without hurting the plant.
BEST VARIETIES: 'Victoria', with its greenish red stalk, is a standard. Heavy-producing 'Cherry Red' is excellent-flavored. 'MacDonald', 'Valentine', and 'Crimson Red' are all very red.