Tall Species with Dwarf Features

This article was first published on 10 Nov 2011.

If your idea of a rhododendron is one of big showy flowers and broad oval leaves you may well walk past Rhododendron genestierianum without even noticing it. If you do happen to stop where it is growing at the southern exit of Dunedin Botanic Garden’s Azalea Garden, you might even wonder if it is a rhododendron at all. One of the rewards of developing a large plant collection though, is in growing the unusual along with the familiar to enjoy a broader appreciation of their variations.

Rhododendron genestierianum is unlike any other species. They grow to 2m or more, but the thimble-like flowers look more as if they belong on a ground hugging dwarf species. From a distance, what look like small ovoid fruit, are actually the unopened flowers which come out on each truss in a succession of three or four at a time rather than all at once. Dangling on the ends of long stalks, they look like small plum-purple coloured lamps. Each flower is also shaded a subtle bluish-white by a fine powdery covering, similar to that on grapes.

The same whitish coating lightens the undersides of the mature leaves, whilst the new growth comes out an almost translucent light green. Often appearing at the same time as the flowers, these whorls of new foliage make a light airy contrast to the small dark blooms. Linking the two though, are remnant leaf bracts which hang below the new leaves and whose light pink colour complements the deeper flower tones.

Doug Thomson is curator of the Rhododendron Dell at Dunedin Botanic Garden.