Apocynum cannabinum aka Indian Hemp

Apocynum cannabinum is a bushy perennial in the dogbane family. Its common names include Indian hemp and hemp dogbane. Its native range runs from subarctic North America to northern Mexico. It grows across the lower 48 states and much of Canada. Wild plants grow in prairies, open woods, and rocky clearings. They also grow along streams and on disturbed ground.

Plants often reach 2–4 feet (0.61–1.22 metres) tall in gardens. NC State also lists heights up to 5 feet (1.52 metres). Their spread reaches about 2.5 feet (0.76 metres). Stiff, upright stems form a bushy clump with branches near the top. The smooth stems are red and hold milky sap. Green leaves grow in pairs along each stem. Their shapes range from narrow and pointed to oval. Leaf edges are smooth, and the undersides bear hairs. Lower leaves have short stalks; upper leaves lack them. The leaves turn yellow in fall, then drop.

Small white to green flowers form clusters at the stem tips. More clusters grow where upper leaves meet the stems. Each flower has a tube or small bell shape. Bloom dates differ between sources, spanning May through August. Bees, butterflies, and other insects visit the flowers for nectar. Paired, slim pods hang from the stems and curve slightly. They reach 0.33–0.67 feet (0.10–0.20 metres) long. Brown seeds have white hair tufts that help wind carry them. Dead, hollow stems also give native bees places to nest.

Full sun and well-drained soil suit this plant best. It prefers sand but also grows in loam and clay. NC State lists partial shade as another suitable light level. Dry to moist soil suits it, and it tolerates drought. Missouri Botanical Garden lists USDA zones 4–9; NC State lists 3–11. Rhizomes spread fast and can crowd nearby plants. This makes it better suited to natural areas than mixed beds. It can help hold soil on slopes and stream banks. Sources report no major pest or disease problems.

People have used its fibres for rope, thread, nets, and paper. Indigenous peoples also used the plant in medicine. These past uses do not establish safe home use. All parts contain poisons that can harm the heart. Sap can blister skin, and ingestion can cause severe illness. The plant also poses a risk to pets and horses. NC State calls it non-edible, while PFAF records seed and gum uses. Those reports conflict with clear warnings that all parts are poisonous.