Species Native to Missouri
Common Name: purple milkweed
Type: Herbaceous perennial
Family: Apocynaceae
Native Range: Eastern North America
Zone: 3 to 8
Height: 2.00 to 3.00 feet
Spread: 1.00 to 3.00 feet
Bloom Time: May to July
Bloom Description: Rose-pink to purple
Sun: Full sun
Water: Dry to medium
Maintenance: Low
Suggested Use: Naturalize
Flower: Showy
Attracts: Butterflies
Tolerate: Deer, Drought, Erosion, Dry Soil, Shallow-Rocky Soil
Culture
Easily grown in average, dry to medium moisture, well-drained soils in full sun. Does well in poor, dryish soils. Drought tolerant. Easily grown from seed, and will self-seed in the landscape if seed pods are not removed prior to splitting open. Can spread somewhat rapidly by rhizomes. Often forms extensive colonies in the wild.
Noteworthy Characteristics
Asclepias purpurascens, commonly called purple milkweed, is a rough, weedy, Missouri native perennial that commonly occurs in dry to moist open woods, dry ridge tops, thickets, glades, prairie openings, stream banks and wet meadows throughout most of the state (Steyermark). It is similar in appearance to common milkweed (A. syriaca), except its flowers are deep rose pink and its leaves are more pointed. It typically grows 2-3’ tall on stout, upright stems with heavy, pointed, short-stalked, ovate to oblong-lanceolate, opposite leaves (to 8” long). Leaves are dark green above and slightly pubescent below. Stems and leaves exude a milky sap when cut or bruised. Tiny, deep rose-pink flowers appear in many-flowered umbels in May-July. Each tiny flower (to 3/4” long) has 5 reflexed petals and 5 purple heads. Flowers give way to smooth seed pods (to 6” long) which split open when ripe releasing their numerous silky-tailed seeds for dispersal by the wind. Seed pods are valued in dried flower arrangements. Flowers are a nectar source for many butterflies and leaves are a food source for monarch butterfly larvae (caterpillars).
Genus name honors the Greek god Asklepios the god of medicine.
Specific epithet means purple.
Problems
No serious insect or disease problems. Somewhat weedy and can spread.
Uses
Butterfly gardens, meadows, prairies, or naturalized/native plant areas. This plant is considered by many gardeners to be too vigorous and weedy for borders.