Plant Highlights

'Powis Castle' is a bushy, woody-based perennial or subshrub which is grown for its aromatic silvery foliage and is essentially evergreen in our climate. It will flower but sometimes sparsely. Foliage is finely divided and feathery in appearance. Typically grows in a shrubby mound to 2-3' tall and as wide, but spreads by underground rhizomes and may reach 3-6' wide if not restrained. Best grown in poor to moderately fertile, dry to medium moisture, well-drained soils in full sun. Excellent soil drainage is essential for growing this plant well as it does poorly in moist to wet soils where plants are susceptible to root rot. Plant stems tend to lodge (fall) in the summer, especially if grown in fertile soils and/or part shade. Prune plants in spring to control growth, but be careful to leave sufficient numbers of live buds on each stem to facilitate bushy growth. Never prune stems to the ground. Foliage may also be lightly sheared in summer to shape, but avoid pruning in fall. This is not a California native but is seen in many California drought tolerant gardens.