Rhododendron [Gk, "red tree"] is a large genus (700 species) of the heath family (Ericaceae) found in the Northern Hemisphere; 4 species are native to Canada. The genus contains both rhododendrons, usually evergreen, and azaleas, which are deciduous. Rhododendrons range from creeping shrubs to medium-sized trees, with saucerlike to bell-shaped flowers (white, pink, red, mauve, purple, yellow to orange). Rhododendrons possess a wide range of leaf types, all simple, often leathery, and frequently covered with soft hairs (indumentum) or scales. Larger-leaved species frequently exhibit very tight enrolling of leaves during freezing weather, an adaptation that prevents water loss. Indian azalea (single- and double-flowered), derived from R. simsii, is sold as a pot plant at Christmas. Many variously coloured outdoor hybrids have been produced. Species and hybrids are significant ORNAMENTALS in Canadian gardens, particularly in milder coastal regions. Most rhododendrons are propagated by cuttings.