Asclepias speciosa

(Showy Milkweed)

_DSC1056%20copy

Asclepias speciosa, North of Paonia, Delta Co. 2829

D81_1060%20copy

Asclepias speciosa, North of Paonia, Delta Co. 2819

_DSC1056%20copy

Asclepias speciosa, Newcastle-Buford Rd., Garfield Co. 6245

_DSC1056%20copy

Asclepias speciosa, Newcastle-Buford Rd., Garfield Co. 6229

_DSC1056%20copy

Stem Leaves, Asclepias speciosa, North of Paonia, Delta Co. 2861

_DSC1056%20copy

Asclepias speciosa, Newcastle-Buford Rd., Garfield Co. 6247

Scientific Name Asclepias speciosa USDA PLANTS Symbol ASSP
Common Name Showy Milkweed ITIS Taxonomic Serial No. 30304
Family Apocynaceae (Dogbane) SEINet
Reference
Click Here
Description Life zones and habitat: Plains and foothills (3400 to 8400 ft); moist soils of prairies, roadsides, waste areas, lake margins.
Plant: Erect perennial, 16 to 48 inches tall; slightly to densely hairy stems with milky sap.
Leaves: Stem leaves opposite, petiolate, oblong-lanceolate to ovate-oblong, 4 to 8 inches long and up to 4 inches across; with transverse veins.
Inflorescence: Several umbels on peduncles 1 to 3 inches long; 5 greenish sepals often hidden beneath pink to purplish-red petals that are about 1/2-inch long; 5 pale pink to white hoods spreading in a star pattern, each 1/3 to 1/2-inch long; white, sickle-shaped horns, shorter than hoods, arching over anther head. See Orbis Environmental Consulting's website for a discussion of milkweed flower morphology.
Bloom Period: June to August.
References: "Flora of Colorado" by Jennifer Ackerfield, Burke Museum-Washington University and Kansas Wildflowers and Grasses.
BONAP Distribution Map


Map Color Key
Colorado Status:
Native

© Tom Lebsack 2022

Banner photo: Ten Mile Range and Rhodiola integrifolia (King’s Crown) in Summit County