Smooth Sumac Plant Care

Smooth Sumac (Rhus glabra) belongs to the Anacardiaceae family within the Rhus genus. Smooth Sumac is also known as Scarlet Sumac, Red Sumac, Upland Sumac.

Smooth Sumac displays an upright, spreading shrub or small tree growth habit, reaching up to 15 ft tall with a spread of approximately 10 ft. Smooth Sumac produces small clusters of greenish-yellow flowers.

Leaf size: approximately 6 inches.

Water a young or newly planted Smooth Sumac every 7–14 days, soaking the whole root zone, until it is established — usually one to two growing seasons. Established trees mainly need water during long dry spells. In a container, water whenever the top few centimetres of soil are dry.

Smooth Sumac thrives in full sun to partial shade.

Rhus glabra tolerates temperatures of 50–90°F. Smooth Sumac prefers humidity levels of 40–70%.

Well-draining sandy soil with added organic matter like compost or peat moss. Good drainage is essential for Smooth Sumac to prevent waterlogging, which leads to root rot and fungal issues.

Feed Smooth Sumac every 8 months during the growing season with a balanced, slow-release fertilizer at the rate on the label. Established trees in good soil often need little extra feeding, so let weak growth or pale foliage guide you.

Stop feeding by late summer so new growth can harden before winter.

The PlantoScan app can remind you when to water and when to fertilize each plant.

Choose a spot with full sun to partial shade and well-draining sandy soil with added organic matter like compost or peat moss. Avoid low spots where water collects after rain.

Smooth Sumac is suited to USDA Zone 12a.

Plant container-grown or balled-and-burlapped trees in spring or early autumn, setting the root flare at soil level, and water well after planting.

Smooth Sumac can spread to about 10 ft (3 m) and reach about 15 ft (5 m) tall. Space plants about 10 ft (3 m) apart so mature crowns don't crowd each other, and plant at least half that distance from buildings, fences and paths.

Planning a row or hedge? Try the tree spacing calculator.

Prune Smooth Sumac while it is dormant in late winter: first remove dead, damaged and crossing branches, then thin lightly for shape.

If it flowers in spring, prune right after flowering instead so you don't remove next year's buds. Never take off more than about a quarter of the tree in one year.

Smooth Sumac is frost-tender (hardy to USDA zone 12). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Smooth Sumac can be propagated through seeds, root cuttings. Similar propagation techniques also apply to fragrant sumac plant care, which shares the same genus.

See all plants toxic to cats and plants toxic to dogs.

Smooth Sumac is susceptible to aphids, scale insects, caterpillars. Inspect the foliage regularly, especially along leaf undersides and stems. Treat infestations promptly with insecticidal soap or neem oil to prevent spread.

Yellow leaves, brown tips or drooping? See common plant problems and how to fix them.

Smooth Sumac grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. In cooler regions, grow Smooth Sumac as a houseplant or bring it indoors before the first frost.