Cumberland Azalea

Size, growth and what to expect

It grows slowly, and our growth estimator treats it as about a foot a year. It grows 3 to 7 feet tall and 3 to 6 feet wide. It often spreads from underground stems into colonies.

Clusters of three to seven red to orange funnels open in June and July, after the leaves are out and later than other azaleas. Each is up to 1.75 inches across, with long stamens. Its capsules show from July to October.

It grows wild mainly on the Cumberland Plateau and mountains of Kentucky, Tennessee, Virginia and Alabama. A few stands grow farther east, in the Blue Ridge of Virginia, North Carolina, South Carolina and Georgia. Its home is open oak woods near ridge tops, from about 1,000 to 5,900 feet.

How to grow Cumberland Azalea

Cumberland azalea does best in part shade in the South and takes full sun farther north. It wants a moist, acid soil rich in organic matter that drains well, and it needs water in a drought. Set plants 5 feet apart and keep them 3 feet from a wall. At its size it can go within 15 feet of overhead wires.

Saplings ship potted. Plant dormant plants in early spring or fall, in a hole three times as wide as the root ball and no deeper. Set the top of the ball a touch above grade, and put the native soil back in. Mulch with pine needles or leaves, kept off the stems. Seed is the best way to raise it, since cuttings root poorly. The seed is dust-fine and needs light but no chilling. Sow it in winter on the surface of damp milled sphagnum, uncovered, under a clear cover at room temperature. Seedlings come up in one to three weeks.

Water weekly through the first two summers, and more often in a drought. Prune only lightly, and only right after bloom, since next year's flower buds form by late summer.

Each flower carries both male and female parts, and it draws butterflies, moths and hummingbirds. Sources disagree on whether a native azalea sets seed with its own pollen, so plant two seedlings from different parents for seed. It is a host plant for the azalea caterpillar and the rhododendron borer. Root rot takes plants in soil that stays wet. Every part of the plant is poisonous if eaten.