Wormwood (Artemisia ‘Powis Castle’)

Features and Characteristics

Artemisia is a genus containing about 200 species of evergreen and deciduous shrubs, perennials and annuals mostly native to dry temperate regions of the Northern Hemisphere. Many of the species feature aromatic, pinnately divided or finely dissected silvery-green foliage and non-showy flowers.

Genus is named for Artemis, Greek goddess of the moon, wild animals and hunting.

‘Powis Castle’ is most likely a hybrid between Artemisia arborescens (large wormwood) and Artemisia absinthium (absinthe wormwood). It is a bushy, woody-based perennial or subshrub that is primarily grown for its aromatic, finely-divided, silvery, fern-like foliage which is feathery in appearance. It typically grows in a shrubby mound to 2-3’ tall and as wide, but spreads by rhizomes and may reach 3-6’ wide if not restrained. Tiny yellow-tinged silver flowers rarely bloom. Plants are essentially evergreen in warm winter climates.

‘Powis Castle’ was introduced in 1972 from the National Trust’s Powis Castle in Wales. Allan M. Armitage considers ‘Powis Castle’ to be “one of the finest plants in cultivation.” 1993 RHS Award of Garden Merit.