Professor Sargent (Trees and Shrubs, Vol. 2, p. 137, t. 156) figured and described this as a new species in 1913. It is closely allied to H. virginiana, but is a native of Missouri, Arkansas, and Louisiana, and resembles the Asiatic species in flowering on the leafless wood from January to March. It differs from H. virginiana also in the following respects: the inner surface of the calyx-lobes is red, and it has the habit of spreading by suckers or underground stems. The leaves are of a paler duller green. It grows naturally on gravelly, often inundated banks of streams, and was collected by Engelmann in Missouri as long ago as 1845. The flowers have a pungent, not very agreeable odour. Bot. Mag., t. 8573.
H. vernalis was introduced to Kew in 1910 but has never been common in British gardens. According to Dr Wyman (Shrubs and Vines for American Gardens (ed. 1969), p. 237) the flowers ‘have the interesting quality of opening fully on warm sunny days, and closing or rolling their petals together on cold days, and so remain effectively in bloom for several weeks’. The petals vary in colour in the wild from yellow to reddish, or may be red at the base and yellow at the ends. The leaves are permanently stellate-downy beneath in f. tomentella Rehd. Although plants that grow naturally in wet habitats do not necessarily need or even tolerate such conditions in our climate, H. vernalis, on its own roots, is perhaps worthy of trial for decorating the edges of reservoirs.
cv. ‘Sandra’. – Young leaves flushed with plum-purple. Autumn colour orange, scarlet, and red. Raised by Messrs Hillier (Lancaster, op. cit.,pt 4, p. 27).