A sub-evergreen shrub up to 5 ft high, with slightly angled, branching stems. Leaves slightly to strongly aromatic when crushed, deep green, 11⁄2 to 3 in. long, ovate, blunt or rounded at the tip, sessile. Flowers borne in abundant cymes at the ends of the shoots, and in the axils of the terminal leaves, one to three flowers in each final subdivision of the inflorescence; they are yellow, 1 in. across; sepals narrowly to broadly ovate, persistent at least until the fruit ripens; petals longer than the sepals, which are ovate, reflexed in fruit; styles three, about twice as long as the ovary or slightly longer. Fruits dark brown or reddish, not quite so persistently fleshy as in H. androsaemum, and longer and more tapered at the top.
A variable hybrid between H. androsaemum and H. hircinum which occurs in the wild where the two species are in contact and has also arisen in gardens, no doubt at many times and in many places. It was in cultivation and in commerce by the mid-18th century and has become naturalised in some of the rainier parts of the British Isles, e.g., in Cornwall, Argyll, Perthshire, and Co. Down. It is also found in apparently wild conditions in Madeira.
H. × inodorum is sometimes confounded with H. androsaemum, but is distinguished by its flowers, which have sepals shorter than the petals, stamens longer than the petals and styles twice or slightly more the length of the ovary; it is also of somewhat taller growth. But it resembles H. androsaemum and differs from H. hircinum in its persistent sepals; also, its leaves lack the goat-like smell of H. hircinum, though they are often aromatic. H. × inodorum is mainly represented in cultivation by the cultivar ‘Elstead’, raised by W. Ladhams of Elstead, which received an Award of Merit in 1933. This is of dwarf habit and the ripening fruits are soft orange-scarlet. It is this variety that is figured in Botanical Magazine, n.s., t. 376. Unfortunately it is subject to a rust disease which discolours the leaves and weakens the plant.