Clethra - Lily Of The Valley Tree, Summersweet, Sweet Pepper Bush, White Alder

(Cle'thra)

DESCRIPTION: This group consists of about sixty evergreen and deciduous shrubs and trees found wild in the southern U.S., Central and South America, Madeira, and Southeast Asia. Clethra, commonly known as White Alders, produces clusters of tiny, fragrant, white or pale pink flowers, in the summer. Some varieties have attractive, peeling bark. C. alnifolia (commonly known as Summersweet and Sweet Pepper Bush) is a hardy, deciduous shrub that rarely grows over 6 feet high. Its dark green, ovate-shaped leaves turn yellow and orange in the fall. In late summer, terminal panicles of white, or nearly white, flowers are borne. C. delavayi is a gorgeous, large, deciduous tree that produces long racemes of white flowers that resemble Lilies of the Valley. They grow horizontally at the ends of branchlets. This variety needs a sheltered location and protection from late spring frosts.

POTTING: These plants need soil that is free of lime; lime-free loam, which has been enhanced with liberal amounts of peat moss or compost is best. Since Clethras produce roots close to the surface, it would be beneficial to provide a thick layer of mulch, in early June, to keep the soil moist and cool. Regular pruning isn't required, though the older wood of established plants can be thinned out to improve their shape once they have finished blooming. The new shoots should be left unpruned to provide flowers the next year. Growths can be removed from the base in the winter. Very old plants can be rejuvenated by cutting back hard in the spring and fertilizing well.

PROPAGATION: Seeds may be sown in early spring, in sandy peat, and placed in a cool greenhouse or frame. Cuttings may be made of leafy shoots, 3 or 4 inches long, with a thin "heel" of old wood attached. These can be inserted in a closed frame in the summer. Some varieties of Clethra spread by means of underground stems, therefore, producing suckers freely. These clumps of suckers may be lifted and planted, in March.

VARIETIES: C. alnifolia & var. paniculata, rosea; C. barbinervis (Japanese Clethra, Japanese Sweet Pepper Bush); C. delavayi; C. fargesii; C. tomentosa; C. arborea (Lily of the Valley Tree).

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