Apocynaceae : Apocynum androsaemifolium
Family Name
Apocynaceae
Common Name
Spreading dogbane
Description
Apocynum androsaemifolium is a perennial herb, somewhat woody dichotomously branched stems coming from rhizomes, ascending to erect and growing from 15-90 cm tall. They are smooth, light green to red in color. The leaves are simple, opposite usually with entire margins. The leaves generally droop but can be horizontal, having short petioles and are ovate to elliptical in shape, 1-9 cm long and 0.5-5 cm wide. Inflorescences are generally terminal (with some axial) open cymes. The flowers are drooping to somewhat erect. The 5-merous calyx is fused with lobes 1-3 mm long. The corolla is whitish-pink to pink with pink veins internally, broadly campanulate, 5.5-8.8 mm long and 4-8 mm wide, with lobes that are up to half the length of the tube. The fruit is a pendulous, usually straight follicle, 6-14 cm long. Spreading dogbane blooms from June to September, the seeds (2-4 mm long) emerge from the follicles in late summer and fall. They are covered in white hairs that are ~ 2 cm long. Plants can be found in prairies, at the edge of woodlands and around lakes and streams in both east and west river in South Dakota.
Horticulture Notes
Seed collection: Collect seeds after the follicle opens.
Germination: Seeds have limited dormancy and can be planted out in fall or spring.
Vegetative Propagation: Clusters can be divided and transplanted in the spring,
Light: Full sun to shade.
Soil Moisture: Dry
Water Use: Medium
Soil: Sandy or gravelly soils.
Additional Notes
Spreading dogbane has white milky sap that contains several phytochemicals that can be poisonous if consumed and can cause skin irritation and blistering. Fibers in the stems were used by several North American tribes as a source of thread. The flowers and the red stems make a colorful addition to a garden, attracting butterflies and bees. This species can be quite aggressive in a garden and can spread rapidly.