Succeeds in ordinary garden soil but prefers a well-drained woodland soil and some shade. Plants succeed in maritime gardens. Hardy to at least -20°c. Plants seem to be immune to the predations of rabbits. A greedy plant, inhibiting the growth of nearby plants, especially legumes. A good woodland plant.

None known

Seed - best sown in a cold frame as soon as it is ripe in the summer. Surface sow or only just cover the seed and keep the soil moist. Sow stored seed as soon as possible in late winter or early spring. The seed usually germinates in 1 - 6 months at 15°c. When large enough to handle, prick the seedlings out into individual pots and grow them on in light shade in the greenhouse for at least their first year. When the plants are large enough, plant them out in the spring. Division in late summer after the plant dies down.

Prairies, dry, open woods, pastures and roadsides at elevations from 300 - 3000 metres.