Dwarf azaleas are hybrid varieties of regular azaleas. Their growing zones are more limited than the larger hardy azaleas, but they last for many years when planted in those areas. Dwarf azaleas do well growing under windows, as border plants and they can be grown in containers as well.
Kurume azaleas are compact growing, twiggy shrubs. The leaves resemble those of the boxwood hedge and the flowers, which bloom in the spring, are small but there is a profusion of blooms. The kurume azaleas are hardy in zones 5 to 10, from the lower Mid Atlantic States to the tip of Florida and in some places along the west coast. The can be grown further north if they are given winter protection, under glass or wrapped in tar paper and burlap. Different varieties will produce different colors. Avalanche is white, coral bells is pink, hexe is crimson, hino-crimson is bright red, seraphim is purple, Sherwood orchid is violet, singing fountain is salmon, snow is white, and Ward's ruby is red.
While they are a dwarf, they have been known to reach a height of from 4 to 6 feet. They need filtered, partial sun not direct sunlight and soil that is constantly moist.
Gumpo azaleas bloom later than other varieties, with flowers appearing in late May and June. Gumpo is a spreading evergreen shrub that will hardly ever get taller than 2 feet high and 3 feet wide. The leaves are the same as those of the regular azalea plants only smaller, usually less than 1 ½ inches long. The plant produces flowers that are ruffled and 3 inches wide. The flowers can be white, pink or red and can be speckled with other colors. Gumpo azaleas are only hardy as far north as zone 7. They need the same soil as other azaleas, well drained and moist.
Satsuki azaleas are an evergreen that have been grown in Japan for hundreds of years. They bloom from mid May through June and produce flowers that can be from 1 to 5 inches in diameter. The lobes of the flowers can be rounded and overlapping or narrow and wide spaced. They can also be flat of frilled. The colors can be white, pink, yellow/pink, red, /red/orange or purple and the patterns can be solids, stripes, flakes, lines, sectors or margins of a contrasting darker color. The same plant can produce different colors and patterns in different years.
The leaves of the satsuki can measure from ½ to 2 inches in length and the shapes can be narrow and oval tapering to a point, egg shaped and flat or egg shaped. Some produce leaves that are twisted, some can be variegated and some can be blotched or have margins in yellow.