Clematis texensis aka Crimson Clematis

Clematis texensis is a woody vine in the buttercup family. Common names include Texas clematis and scarlet leatherflower. It comes from the southeastern Edwards Plateau in Texas. There it grows on limestone cliffs, rocky slopes, and stream banks. This perennial climbs fast and sheds its leaves each year. Its older name is Clematis coccinea.

Garden height ranges from about 5–9 feet [1.5–2.7 metres]. Sources give widths of 2–5 feet [0.6–1.5 metres]. The lower stems become woody and bare. Leaf stalks twist around supports to help the vine climb. The leaves grow in opposite pairs along the stems. Their grey-green blades divide into oval leaflets with smooth edges. Leaves may be pinnate or twice pinnate. They reach about 2.5 inches in length.

Flowers hang from long stalks marked with raised ribs. They resemble small bells or pitchers, with thick, leathery sepals. The outer surface ranges from crimson to scarlet-orange. White edges frame cream or pink inner surfaces. Yellow stamens sit within each flower. Bloom runs from July through September, sometimes lasting until frost. Small brown achenes follow the flowers in autumn. Each dry fruit has a soft, feathery tail. Both flowers and fruit add interest to the garden.

Grow this vine in well-drained soil with neutral or alkaline pH. It accepts loam, sand, and shallow rocky ground. Sources recommend full sun through partial shade. Keep the roots cool and the site sheltered. It tolerates drought, though garden water needs are moderate. Sources rate it for USDA zones 4–8 and UK H4. RHS advises dry winter mulch over the crown. Cold sites may need protected winter storage for container plants. Flowers form on new shoots; NCSU recommends pruning in late spring. Train it over fences, trellises, arbors, or rock walls. It also threads through shrubs and suits small gardens.

Aphids, snails, caterpillars, and earwigs can damage this plant. Wilt, stem rot, and powdery mildew may also occur. RHS lists slime flux and rare honey fungus infections. Deer may damage it less often than other plants. Its leaves are poisonous, and contact can irritate skin. Eating it can harm people, dogs, cats, and horses. NCSU records stem tea use for headaches and migraines. That historic use does not establish safety as food or medicine.