AZALEA  , a genus of popular

hardy or greenhouse plants, belonging to the heath order (Ericaceae), and scarcely separable botanically from Rhododendron . The beautiful varieties now in cultivation have been bred from a few originals, natives of the hilly regions of China and Japan, Asia Minor, and the United States . They are perhaps unequalled as indoor decorative plants . They are usually increased by grafting the half-ripened shoots on the stronger-growing kinds, the shoots of the stock and the grafts being in a similarly half-ripened condition, and the plants being placed in a moist heat of 65° . Large plants of inferior kinds, if healthy, may be grafted all over with the choicer sorts, so as to obtain a large specimen in a short time . They require a rich and fibrous peat soil, with a mixture of sand to prevent its getting water-logged . The best time to pot azaleas is three or four weeks after the blooming is over . The soil should be made quite solid to prevent its retaining too much water . To produce handsome plants, they must while young be stopped as required . Specimens that have got leggy may be cut back just before growth commences . The lowest temperature for them during the winter is about 350, and during their season of growth from 550 to 65° at night, and 750 by day, the atmosphere being at the same time well charged with moisture . They are liable to the attacks of thrips and red spider, which do great mischief if not promptly destroyed. rr The following are some well-known species:—A. arborescens (Pennsylvania), a deciduous shrub 10-20 ft. high; A. calendulacea (Carolina to Pennsylvania), a beautiful deciduous shrub 2-6 ft. high, with yellow, red, orange and copper-coloured flowers; A. hispida, a North American shrub, 10-15 ft. high, flowers white edged with red; A. indica (China), the so-called Indian azalea, a shrub 3-6 ft. or more high, the original of numerous single and double varieties, many of the more vigorous of which are hardy in southern England and Ireland; A. nudiflora, a North American shrub, 3-4 ft. high, which hybridizes freely with A. calendulacea, A. pontica and others, to produce single and double forms of a great variety of shades; A. pontica (Levant, Caucasus, &c.), 4-6 ft. high, with numerous varieties differing in the colour of the flowers and the tint of the leaves; A. sinensis (China and Japan), a beautiful shrub, 3-4 ft. high, with orange-red or yellow bell-shaped flowers, hardy in the southern half of England, large numbers of varieties being in cultivation under the name of Japanese azaleas .