Agaves. Peggy Petitmermet grows century plant (Agave americana, both blue-gray and variegated varieties); A. tequilana (with upright, swordlike leaves); and foxtail agave (A. attenuata), so named because of its fuzzy-looking, arching bloom spike. A. montana is dark green and hardier—surviving temperatures as cold as -10°F—with a crimson tooth line and leaf margin.
Candelabra tree (Euphorbia ingens). These tall, slender succulents resemble the saguaro cactus of the desert Southwest. "They remind me of people dancing," Peggy says.
Echeverias. These succulents native to Mexico resemble fleshy roses; larger varieties get as big as cantaloupes. Flowers attract hummingbirds.
Nopal cactus (Opuntia ficus-indica). This prickly pear cactus makes a great fence (to 10 feet high) and, like most succulents, starts easily from cuttings. For colder climates, try O. humifusa (hardy to -45°F). It is native to the eastern United States and has bright green pads and vivid yellow blooms.
Soapweed (Yucca glauca). Grows 3 or 4 feet tall and features stiff, 2-foot-long leaves atop a short trunk and 3-foot-tall flower stalks of creamy blossoms. Hardy to -35°F.