The climate of eastern North America imposes great demands on plants. Occasional warm spells in the depths of winter mustn’t waken the plants, because the following week the temperature might plunge to -30 °C. The rhododendron species native to the area, including the Carolina rhododendron, are rated among the world’s hardiest. It is stated in the USA to be hardy to -31 °C, and new growth and flowers are exceptionally hardy.
The Carolina rhododendron belongs to the so-called lepidote group, characterised by surface scales, whose successful representatives in Finland are usually sub-shrubs, small-leaved with small flowers. By comparison, the Carolina rhododendron is large, large-leaved and large-flowered, usually pink or white. Flowering generally occurs in Finland in early June.
The decorative value of the species is affected by its tendency to drop all the previous season’s leaves in autumn. In winter it is not particularly noteworthy, but the summer show makes up for this. The genes of this species are found in many hardy varieties, among them the well-known PJM-group.
