Clematis columbiana aka Rock Clematis

Clematis columbiana, or rock clematis, belongs to the buttercup family. It is native to western-central and south-central parts of the United States. This deciduous vine grows in woods and thickets. Its wild sites range from dry to moist ground. It occurs in valleys and mountains, reaching about 8,200 feet [2,500 metres]. In gardens, it reaches about 10 feet [3 metres]. Virginia Tech gives a taller limit of 12 feet [3.7 metres]. It can creep along the ground or climb low supports.

The vine grips twigs and branches with curling leaf stalks. Its thin, wiry stems have many ridges. Young stems start green, then turn reddish brown. Smooth young bark later develops long cracks. The leaves grow in opposite pairs and fall each year. Each leaf has three leaflets. These range from oval to heart-shaped, with smooth edges. Some leaflets have deep lobes instead.

The pale purple flowers hang down from the stems. Each flower has four pointed sepals with fine hairs. Plants For A Future gives June to July as flowering time. Sources disagree on how the plant bears its sexes. Virginia Tech reports that male and female flowers usually grow on separate plants. Plants For A Future describes flowers with both sexes. It also lists bees and flies as pollinators. Small, dry brown seeds follow the flowers. Each seed carries a long, white, feathery tail. Together, they form loose heads that add interest after bloom.

Grow this vine in sun or partial shade. It suits woodland gardens and shaded edges. Give it deep, moist soil with good drainage. Keep its roots shaded. It grows in acid, neutral, or alkaline ground, including chalk. Plants For A Future warns against light sand and poorly drained clay. It notes that added grit can improve clay drainage. The same source lists USDA zones 4–8. It advises deeper planting to help guard against clematis wilt. Seeds, stem cuttings, and layering offer ways to raise new plants.

Plants For A Future lists no known food uses. Its toxicity warning draws on related clematis, not reports for this species. This leaves species-specific safety uncertain. It records past use of leaves for foot and skin treatments. These records do not establish safe or effective medical use. The seed fluff has served as tinder and shoe insulation. The source also records plant washes for hair care.