Asclepias

Asclepiadaceae
Perennials, Flowers

Milkweeds (so named for their milky sap) are the best-known representatives of this group of plants. Bloom in summer, typically bearing many small, starlike flowers in broad, flattened clusters at branch tips. All have inflated seedpods with silky seeds. Just a few species are cultivated in gardens.

Asclepias currassavica

Zones 8, 9, 12–24; H1, H2; all zones as annual. Native to South America. Woody-based plant with stiff stems and narrow 6-in. leaves; grows 3 ft. tall, 2 ft. wide. Clusters of vivid red flowers.

Asclepias speciosa

Native to western and central North America. This striking perennialgrows 2–4 ft. tall and not quite as wide; may spread by underground stems to form colonies. Thick, upright stems hold big,softly hairy leaves of gray; summer flowers are 3-in.-wide balls of fragrant, purplish pink. Long winter dormancy; new shootsmay not appear until midspring. Needs only occasional wateronce established.

Asclepias tuberosa

Native to eastern U.S. From a perennial root, many herbaceous stems rise every year to form a clump about 3 ft. tall, 1 ft.wide. Clusters of bright orange flowers attract swarms of butterflies. All types make long-lasting cut flowers. Provide good drainage.

Gay Butterflies strain features yellow, red, orange, pink, or bicolored blossoms; ‘Hello Yellow’ has bright yellow blooms.