Roseshell 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. It makes an upright, rounded shrub 3 to 10 feet tall and 4 to 8 feet wide, and now and then 15 feet. Its bright green leaves are grayish and woolly beneath and turn bronze to purplish in fall.

Clusters of 4 to 13 bright pink flowers open from April into June, before or with the new leaves. Each funnel is about 1.5 inches long, with five long stamens, and the scent is spicy, like cloves. Bumble bees find the flowers especially valuable. The slender capsules ripen from August to October.

It grows wild from southern Quebec and New England through the Appalachians to North Carolina, with stands in Georgia and Alabama. A second, separate range runs from southern Illinois and Missouri to Oklahoma and eastern Texas. Its home is acid thickets and bogs, swampy to dry rocky woods, bluffs, ravines and stream banks.

How to grow Roseshell Azalea

Roseshell azalea does best in dappled or part shade, sheltered from the afternoon sun that can scorch its leaves. It also takes full sun or shade. It wants a moist, rich soil that drains well, and it takes soil closer to neutral than most azaleas. It will not stand dense clay or ground where water stands. 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 oak leaves, bark or pine needles, 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, at room temperature under a clear cover. Seedlings come up in one to three weeks.

Water weekly through the first two summers, and never let the shallow roots dry out. Deer damage it often, so cage it where deer are common, though rabbits mostly leave it alone. Prune, if at all, right after it flowers.

Each flower carries both male and female parts, and bees, butterflies and hummingbirds visit the flowers. Sources disagree on whether a native azalea sets seed with its own pollen, so plant two seedlings from different parents for seed. Aphids, lace bugs and mites can mark the leaves, and root rot takes plants in wet, heavy soil. Every part of the plant is poisonous if eaten.