Deciduous ornamental shrubs, some quite old-fashioned, others in unexpected colours.
The old-fashioned species in farm gardens or in old town gardens, the other species in any large or small garden as a specimen plant to provide shade and, in one case, as a climber. Provide sun or partial shade.
Hydrangeas do best in acid, damp soil. They show to best advantage in peaty soil.
Shrubs from winter; the climbing species from taken in summer.
anomala spp petiolaris syn Hydrangea petiolans: A climbing shrub which grows to at least 7 m in height, but initially its growth is slow; white flower umbels, consisting of sterile and fertile florets, in mid summer. Should be tied here and there. Hydrangea arborescens: Height 2-3 m; broad umbels of fertile white in mid to late summer. ‘Grandiflora’ is a better known form; it has broad clusters consisting solely of sterile florets. Must be cut down to 10 cm every spring.
Hydrangea aspera ssp sargentiana syn Hydrangea sargen-tiana: Height 1.5 m;in mid to late summer with broad clusters of white florets along the edge and violet florets in the centre. The are very large, oval in shape, velvety green. May also be cut down very low. •
Hydrangea macrophylla, the indoor hortensia, but there are garden forms which are more winter-hardy: Height to 1.5 m; flowering season mid summer to early autumn. There are strains with dome-shaped flower umbels containing only sterile florets, but in the so-called ‘lacecaps’ the centre of the umbel consists of fertile florets in a different colour. ‘Lilacina’ illustrated is a fine example. Occurs in shades of pink, blue,and white. Hydrangea macrophylla ssp serrata syn Hydrangea ser-rata: Height about 1 m; flowers in late summer and early autumn. The umbels consist of fertile and sterile florets, often in different colours. Resembles the previous species, but the leaves are smaller, thinner and not glossy. Hydrangea paniculata: Height to 3 m; flowers late summer to early autumn. Large, pear-shaped clusters of sterile florets, creamy white, shading to pink. Usually occurs in the form of the cultivar ‘Grandiflora’. Must be cut down to just above the soil every spring.