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 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.
Biennial or short-lived perennial. From southernEurope, northwestern Africa.Soft, scallop-edged, silky...
An attractive weed of roadsides and grain fields, this Mediterranean species has naturalized in North ...
This plant has very fragrant magenta-and-goldflowers on plants to 16 in. high.