Sumatran Kauri Plant Care

Sumatran Kauri (Gymnostoma sumatranum) belongs to the Casuarinaceae family within the Gymnostoma genus. Sumatran Kauri is native to Southeast Asia and the Malesia region.

Sumatran Kauri displays a tall, conical tree growth habit, reaching up to 30 ft tall with a spread of approximately 15 ft. Sumatran Kauri produces inconspicuous flowers.

Leaf size: approximately 6 inches.

Water a young or newly planted Sumatran Kauri 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.

Sumatran Kauri thrives in full sun.

Gymnostoma sumatranum tolerates temperatures of 60–85°F. Sumatran Kauri prefers humidity levels of 40–70%.

Well-draining sandy soil with good aeration. Good drainage is essential for Sumatran Kauri to prevent waterlogging, which leads to root rot and fungal issues.

Feed Sumatran Kauri 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 and well-draining sandy soil with good aeration. Avoid low spots where water collects after rain.

Sumatran Kauri is suited to USDA Zone 13a.

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.

Sumatran Kauri can spread to about 15 ft (4.6 m) and reach about 30 ft (9 m) tall. Space plants about 15 ft (4.6 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 Sumatran Kauri 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.

Sumatran Kauri is frost-tender (hardy to USDA zone 13). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Sumatran Kauri can be propagated through seeds, cuttings. Similar propagation techniques also apply to australian kauri plant care, which shares the same genus.

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

Sumatran Kauri is susceptible to scale insects, mealybugs. 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.

Sumatran Kauri grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. Sumatran Kauri is native to Southeast Asia and the Malesia region. In cooler regions, grow Sumatran Kauri as a houseplant or bring it indoors before the first frost.