Rudbeckia amplexicaulis aka Clasping Leaf Coneflower

Rudbeckia amplexicaulis has the common name clasping coneflower. It is an annual, so it lives for one year. It belongs to the daisy family, Asteraceae. Its native range spans the central and southeastern United States. It grows in temperate regions, where the climate is mild. It is not native to Britain or Ireland. The RHS also uses the name Dracopsis amplexicaulis. The plant suits beds, borders, and native plant areas.

The plant grows upright and has a bushy shape. In gardens, it reaches about 1.6–3.3 feet [0.5–1 metre] tall. Its spread is 0.3–1.6 feet [0.1–0.5 metres]. It has oval leaves whose bases clasp the stems. This shape gives the plant its common name. The RHS calls its leaves deciduous, which means they fall off. Its upright shape suits mixed flower beds and informal borders.

Each single flower head has yellow rays round a large brown disk. Heads measure about 0.16–0.23 feet [0.05–0.07 metres] across. Missouri Botanical Garden lists blooms from July through September. The RHS gives late summer and early autumn instead. The showy blooms add colour to borders and draw butterflies. You can also cut them for use indoors. Suggested sites include cottage gardens and prairie plantings. Wildlife gardens are another choice. The RHS also suggests courtyard gardens and gardens near the coast.

Full sun is the main choice for this plant. The RHS says part shade also suits it. It calls for heavy soil with a fair level of nutrients. The soil should drain well. It lists chalk, clay, and loam as suitable types. The soil can be acid, neutral, or alkaline. The sources differ on how much water it needs. The RHS calls for moist soil that does not dry out. Missouri Botanical Garden gives dry to medium conditions. It also says the plant can cope with drought. The RHS gives a UK hardiness rating of H7. Missouri Botanical Garden gives USDA zones 2–11 for this annual.

Missouri Botanical Garden says the plant needs little care. The RHS says to sow seed in early spring at 16–18°C. Cut plants back once the blooms have finished. Slugs may cause harm, but the RHS notes few disease concerns. Missouri Botanical Garden reports no serious insect or disease problems. Neither source gives facts on edible parts or toxicity. This lack of facts does not mean the plant is safe to eat.