Oxydendrum Arboreum is also known as sourwood, sorrel tree, or lily-of-the-valley tree. It is a member of the Heather Family, Ericaceae. Find facts and information on how to grow and care for this deciduous tree.
Oxydendrum Arboreum Facts
You will find that this tree is beautiful year round. It is elongated, with flower clusters that flip at the tips and has bright fall foliage. Sourwood is narrow and pyramidal with a slender trunk, trim branches, and slim, red or olive-green twigs.
It is hardy in Zones 5-9 and grows 20-30’ h x 10-20’w, and even larger when in the wild. Its origin is in moist, well-drained woodlands in the eastern U.S. Try to provide the same conditions, along with acid soils. The tree thrives in gravelly soils and tolerates some dryness once established. It prefers full sun to part shade.
The tree has an alternate, simple, deciduous leaves, 3-8” long and smooth, and glossy green on the top, change to crimson, purple, and yellow in autumn. They will exhibit the best color when grown in full sun. Sour-tasting leaves have been used as a tonic, an diuretic. The grayish brown bark is smooth when young, becoming plated and grooved with age.
Oxydendrum arboreum has drooping, 10” clusters of white, bell-like, fragrant flower spikes that appear in early to midsummer, held above the leaves. Flowers resemble lily-of-the-valley. It flowers profusely in full sun, and attracts bees and butterflies. Sourwood honey is a southern delicacy.
After flowering, decorative chartreuse capsules, enjoyed by birds, extend the season of interest. By leaf drop, the long-lasting fruit clusters have turned brown, making a subtle but definitely decorative statement on the bare tree.
Uses of Oxydendrum arboreum
This is a fabulous, slow-growing specimen for lawns, against a dark evergreen border, massed in large landscapes, in naturalistic plantings, and along woodland edges.