Group of about 12 species of deciduous or evergreen trees and shrubs from tropical and subtropical parts of the world; the two described here are both U.S. natives. All of these plants are tough and easy to grow. Saponin, a substance contained in the berries, lathers when mixed with waterhence the common name.
S. marginatus. FLORIDA SOAPBERRY. Evergreen. Zones LS, CS; USDA 8-9. Native to the South Atlantic coast, from South Carolina to Florida. Grows 40 ft. tall and 30 ft. wide. Bright green leaves to 14 in. long, each with 7 to 13 lance-shaped leaflets; turn golden in fall. Clusters of small white flowers in spring.
S. saponaria drummondii (S. drummondii). WESTERN SOAPBERRY. Deciduous. Zones US, MS, LS, CS; USDA 6-9. Native to southwestern U.S. and Mexico. Attractive round-headed, spreading tree to 2530 ft. tall and eventually as wide, with yellowish green, 10- to 15-in.-long leaves divided into many leaflets. In early summer, tiny yellowish white flowers bloom in 8- to 10-in.-long clusters; these are followed by beadlike, 12-in., orange-yellow fruit that turns black by winter. Fall foliage is a lovely orange-yellow. Makes a good shade or street tree, thanks to its tolerance for adverse conditions: poor, dry, rocky, alkaline soil; polluted air; wind; occasional drought. Fruit drop and self-sown seedlings can cause problems. 'Narrow Leaf' has narrower leaves than the species.