An evergreen shrub forming a cluster of erect, woody stems to about 4 ft high. Leaves and shoots covered with a close, silky, white down. Leaves cut into linear, bluntly tipped segments, those near the base of the stem distinctly stalked and trebly pinnate, the uppermost sessile and doubly or singly pinnate. Flower-heads bright yellow, globose, short-stalked, 1⁄5 to 1⁄3 in. wide, pendulous at first, later erect, arranged in a leafy, one-sided panicle; receptacles silky-hairy; achenes glandular.
Native of the Mediterranean, where it grows on cliffs and on rocky slopes near the coast; commonest in S. Italy and the Aegean, rarer in the western part of the basin. It is closely related to the common wormwood, A. absinthium, differing mainly in its larger flower-heads and in its non-glandular leaves, which lack the bitter principle characteristic of that species. It is tender but well worth attempting in mild, sunny gardens, best suited under a warm wall in well-drained soil.
From the Supplement (Vol. V)
† cv. 'Faith Raven'. – A reputedly hardier form, introduced by John Raven from the mountains of Crete.
† A. absinthium l. – Wormwood, Absinth – This is less woody than A. arborescens and usually classified as an herbaceous perennial, but it is closely allied to it, differing mainly in the much smaller flower-heads and the less finely cut and less silvery foliage. 'Lambrook Silver', selected by the late Margery Fish, is an improvement on the normal form and hardier than A. arborescens.
A. absinthium is a native of much of Europe, including Britain. The essential oil obtained from it by distillation was the main flavouring of the notorious liquor absinthe, the production of which in its original form was made illegal in many European countries early this century. It is a matter of dispute whether the wormwood itself or the very high alcoholic content of absinthe was responsible for its deleterious effects.
A. 'Powis Castle'. – A hybrid of A. arborescens, probably with A. absinthium as the other parent. The foliage is less silvery than in the former but almost as finely cut, and the plant is much hardier. It makes a low mound 2 to 3 ft high and more in width. Award of Merit in 1983 when exhibited from Kew.