Plumleaf Azalea

Size, growth and what to expect

No source rates its growth, so our growth estimator treats it as slow, like our pinxterbloom azalea, about a foot a year. In gardens it grows 8 to 12 feet tall and 6 to 8 feet wide, upright, open and spreading. Wild plants reach 20 feet.

Clusters of four to seven funnel-shaped flowers open in July and August, orange-red to red with long stamens. The capsules hold tiny seeds with minute wings, likely spread by the wind. It can sprout from the roots, but it does not form thickets.

It grows wild only in the Chattahoochee River valley of Georgia and Alabama, where the river crosses the Piedmont and the Coastal Plain. Its home is moist hardwood ravines with beech, spruce pine and southern magnolia, and wet, sandy stream banks.

How to grow Plumleaf Azalea

Plumleaf azalea does best in part shade, with shelter from afternoon sun, as on a wooded slope above a stream. Too much shade can stop it flowering. It wants a moist, acid soil high in organic matter that drains well, and it will not stand dense clay. Set plants 6 feet apart and keep them 4 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 little above grade, since the roots rot where water stands, and put the native soil back in. Mulch with pine needles or leaves, kept off the stems. 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 never let the shallow roots dry out. Do not overwater or overfeed it, since both invite root rot. Deer damage it often, so cage it where deer are common. Prune, if at all, right after bloom.

Each flower carries both male and female parts, and bees and butterflies carry its pollen. Sources disagree on whether a native azalea sets seed with its own pollen, so plant two seedlings from different parents for seed. Hummingbirds come to the flowers as well. Lace bugs, aphids and mites can mark the leaves, and root rot follows poor drainage. Every part of the plant is poisonous if eaten.