Polygala of the milkwort family is a genus featuring over 500 species of plants (annuals, herbaceous perennials, subshrubs and shrubs) which are widely distributed in warm to temperate regions throughout the world. Plants are generally noted for having alternate lanceolate leaves and pea-like often showy flowers in terminal clusters/racemes.
Polygala x dalmaisiana, commonly called sweet pea bush or milkwort, is a loose, leggy, fast-growing, rounded to spreading, bushy evergreen shrub which typically grows to 3-5’ tall and as wide. It is reportedly a hybrid between two South African species (P. opposistifolia and P. myrtifolia). Stems are clad with ovate dull green leaves (1” long). Terminal racemes of rose-magenta pea-like flowers with two winged petals surrounding a white purple crest bloom summer to frost, but bloom extends to almost year round in mild frost-free climates with minimum temperatures of 40 degrees F. Flowers resemble those of sweet pea.
Genus name comes from the Greek words polys meaning much and gala meaning milk in reference to a belief dating back to the medieval era that ingestion of plant leaves by certain nursing mammals resulted in increased milk production.
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