Piedmont Azalea

Size, growth and what to expect

Piedmont azalea grows slowly, and our growth estimator treats it as slow, about a foot a year. It grows 6 to 15 feet tall, most often 6 to 8 feet in gardens, and 6 to 10 feet wide.

Clusters of 5 to 9 fragrant flowers open from March to May, as the leaves begin to unfold. They are pink, rarely white, 1 to 2 inches long, with the stamens and style arching well beyond the petals. Slender capsules about 1/2 inch long ripen in September and October.

It grows wild from North Carolina to Florida and west to Tennessee, Arkansas and Texas. Its home is moist woods, swamp margins, pocosins, savannas and stream banks, below about 1,600 feet. More than 800 wild stands are known across its range.

How to grow Piedmont Azalea

Piedmont azalea does best in dappled shade or part shade, and it takes full sun where it is shaded from afternoon sun. It wants moist, acid soil high in organic matter that drains freely, and it will not stand dense clay, poor drainage or dry soil. Give it shelter from strong winter winds. Set plants 5 feet apart and keep them 5 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, and put the native soil back in. Spread 3 inches of mulch, kept off the stems, since the roots lie in the top few inches of soil. It is harder to root from cuttings than some wild azaleas, so seed may be the better way to raise it. The seed is dust-fine and needs light, with no chilling. Sow it in winter on the surface of damp milled sphagnum, uncovered, at room temperature under lights and 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. Rabbits leave it alone, but deer damage it often, so cage it where deer are common. Pinch new shoots when they are a few inches long for a bushier plant with more flowers. Prune, if at all, right after bloom, since it flowers on last year's growth.

Each flower carries both male and female parts, and swallowtail butterflies, bees and hummingbirds come to the flowers. Sources disagree on whether a native azalea sets seed with its own pollen, so plant two seedlings from different parents for seed. It crosses readily with other wild azaleas, so seed from a garden with several kinds may give hybrids. Mites are its main pest. Soil that is not acid enough leaves it short of iron, and mushroom root rot takes it where drainage is poor. Every part of the plant is poisonous if eaten, and honey from its flowers can be too.