Attractive flowering plants with showy, drooping clusters of sweet peashaped blossoms that are followed by interesting- looking seedpods. Leaves are divided into many leaflets. Be sure to provide good drainage.
S. affinis. EVE'S NECKLACE. Small deciduous tree. Zones MS, LS, CS; USDA 7-9. Native to the Southwest. Fast growth to 1520 ft. (rarely 30 ft.) tall, with a round canopy to about 15 ft. across. Lustrous, dark green, 3- to 10-in.-long leaves with 13 to 19 leaflets, each 112 in. long. Blooms in late spring, bearing rosy pink to white, lightly scented flowers in pendent, 4- to 6-in. clusters. Lovely, slender, twisted black seedpods grow 36 in. long and look like strings of beads; they hang on through fall and winter. Tolerates thin, dry, limy soils.
S. davidii. DAVID'S MOUNTAIN LAUREL. Deciduous shrub. Zones US, MS, LS, CS; USDA 6-9. From China. Bushy, rounded plant to 812 ft. tall and a little wider. Gray-green, 312-in. leaves divided into 13 to 19 oval leaflets, each under 12 in. long. In late spring or early summer, produces 6-in.-long clusters of small, white, fragrant flowers marked with purplish blue. Long (to 2-in.), narrow pods are constricted between the two to four seeds held inside.
S. secundiflora (Calia secundiflora). TEXAS MOUNTAIN LAUREL, MESCAL BEAN. Evergreen shrub or tree. Zones LS, CS; USDA 8-9. Shrubby, but can be trained into 25-ft. tree with short, slender trunk or multiple trunks, narrow crown, upright branches. To 1520 ft. wide. Leaves are 46 in. long, divided into 7 to 11 oval, glossy, dark green leaflets, each up to 2 in. long. Violet-blue flowers in drooping, 4- to 8-in. clusters reminiscent of wisteria smell like grape juice; midwinter to early spring bloom. Silvery gray, woody, 1- to 8-in.-long seedpods open when ripe to show poisonous, bright red, 12-in. seeds. If possible, remove pods before they mature. Thrives in heat and alkaline soil with good drainage. Choice small tree for street, lawn, courtyard. Old-time favorite in Southwestern gardens, though its floral display may be eliminated or sharply reduced if late freezes hit when the plants are in bud. 'Alba' is a white-flowered form. 'Silver Peso' has silvery foliage.