Clematis serratifolia aka Saw Toothed Clematis

Clematis serratifolia, or Korean clematis, is a deciduous climbing plant. It belongs to the buttercup family, Ranunculaceae. Kew lists its native range as South Korea. Plants For A Future gives a wider East Asian range. This includes parts of Russia, China, Japan and North Korea. That source records hedges, dry woods, slopes and gravelly riverbanks as habitats. It also notes an association with lime-rich soils.

This climber loses its green leaves for winter. The RHS gives a garden height of 8–13 feet [2.5–4 metres]. Its shorter description places the height near 10 feet [3 metres]. Plants spread about 3–5 feet [1–1.5 metres]. They reach full size within two to five years. Soft yellow blooms appear in late summer and early autumn. Each flower measures about an inch long and has purple stamens. The flowers have a citrus scent, which grows stronger in sun. Silky seedheads follow the blooms and add interest after flowering.

Grow this plant in sun or part shade. It needs soil that holds moisture but drains well. The RHS lists chalk, clay, loam and sand as suitable soils. Acid, neutral and alkaline conditions are all acceptable. Keep the roots and stem base cool and shaded. Nearby plants, pebbles or flat stones can provide this cover. The RHS rates its winter hardiness as H6. Plants For A Future lists USDA zones 5–9. The RHS places it in clematis pruning group three.

This species suits courtyard gardens, cottage gardens and borders beside walls. It also fits informal beds and woodland edges with dappled shade. Its late flowers and seedheads extend its season of interest. Growers can raise new plants from seed, cuttings or layering. Aphids, snails and caterpillars may attack it. Earwigs may chew the petals. Possible diseases include clematis wilt and clematis slime flux. Honey fungus is another risk, though the RHS calls it rare.

Treat this plant with care rather than as a food crop. The RHS warns that it can irritate skin. Wear gloves and protective clothing when handling it. It also warns that rabbits can suffer harm from eating it. Plants For A Future lists leaves and cooked young shoots as edible. Yet that source urges caution because of possible toxicity. Its food rating is low, at one out of five. It records no known medicinal or other uses.