Family: Asteraceae
Common Name: Hemp Agrimony

There were previously hundreds of species in this genus but after reclassification, only about 40 remain. Mainly natives of eastern North America, only a few species are suitable for the garden. Although members of the daisy family, the tubular flowers form fluffy heads rather than the distinctive ray floret of the daisy. Species cultivated as ornamentals make good background plants in perennial borders, as their form is substantial and flower colour unusual.

Species

E. cannabinum, hemp agrimony, zone 5, from Europe, is a frost-hardy, herbaceous plant, to 1.5 m (5 ft), with purplish lilac flowers in late summer.

E. megalophyllum, zone 10, a native of Mexico, produces several erect, reddish purple branches. This shrub grows to 2 m (6 ft) high and wide and has broad, ovate, grayish green leaves and striking, flattened clus­ters of fluffy, violet-blue flowers during autumn.

E. purpureum, Joe pye weed, zone 4, is an herbaceous species from North America, with vanilla-scented leaves and a flattish head of pale purple flowers above a spiral of leaves. It grows to 2 m (6 ft). This species, also known as boneset or gravelroot, has a history of use in herbal medicine.

Cultivation

Any frost-tender species are grown in an airy, cool to intermediate greenhouse or conservatory with maximum light. Use soil-based potting compost. Outside, choose a posi­tion with well-drained vet moisture-retentive soil and full sun or partial shade. Propagate by division, or from seed or softwood cuttings according to species.

Climate

There are species suited to various climatic zones.