Rhododendron Smirnowii or Smirnow Rhododendron
The Smirnow rhododendron is native to the south-western Caucasus. It is a shrub or tree growing to a height of 6m (20 ft). The leaves are 15cm (6 in) long, stiff, thickly felted rusty-white on the underside when they open, later becoming bare. Young shoots are also covered with a whitish felt. The, about 6 to 7cm (2¼ to 2¾ in) in diameter, are coloured purplish-pink to reddish-pink and appear in June. Like the this Caucasian species has also given rise to numerous hybrids, derived mostly from crosses with Rhododendron arboreum and . In the majority of hybrids the leaves are rust-felted below; they do not so easily become bare. These rhododendrons are very hardy and particularly well suited for inland regions.
Rhododendrons are also readily propagated by cuttings. These should be taken from well-ripened annual shoots, in September at the earliest but no later than before the first frost. Hormone rooting powder can be applied to assist good rooting and they should then be inserted close together in dishes and put in a propagator in a temperature of about 20° C (68° F). The dishes are covered with glass and a constant humidity is maintained inside by frequent misting, first of all about twice, later three times a day. They should be ventilated so that drops of water do not form on the glass and in sunny weather the cuttings should be shaded. Without rooting powder the cuttings are generally not rooted until March, when they may then be transferred to a frame. It takes two or three years before the seedlings can safely be moved to their permanent site outdoors.