Hawaiian Sumac Plant Care

Hawaiian Sumac (Rhus sandwicensis) belongs to the Anacardiaceae family within the Rhus genus. Hawaiian Sumac is native to Hawaii. Hawaiian Sumac is also known as Aalii.

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

Leaf size: approximately 6 inches.

Water a young or newly planted Hawaiian 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.

Hawaiian Sumac thrives in full sun to partial shade.

Rhus sandwicensis tolerates temperatures of 50–90°F. Hawaiian 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 Hawaiian Sumac to prevent waterlogging, which leads to root rot and fungal issues.

Feed Hawaiian 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.

Hawaiian 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.

Hawaiian 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 Hawaiian 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.

Hawaiian 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.

Hawaiian 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.

Hawaiian 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.

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