Assam Horse Chestnut Plant Care

Assam Horse Chestnut (Aesculus assamica) belongs to the Sapindaceae family within the Aesculus genus. Assam Horse Chestnut is native to warm temperate to subtropical areas of the eastern Himalayas from Sikkim through Bhutan and Assam to Arunachal Pradesh, and southwestern and southern China, Bangladesh, and mainland southeast Asia, except Cambodia and Peninsular Malaysia.

Assam Horse Chestnut displays a large deciduous tree growth habit, reaching up to 50 ft tall with a spread of approximately 30 ft. Assam Horse Chestnut produces showy clusters of white, pink, or red flowers.

Leaf size: approximately 8 inches.

Water a young or newly planted Assam Horse Chestnut 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.

Assam Horse Chestnut thrives in full sun to partial shade.

Aesculus assamica tolerates temperatures of 60–90°F. Assam Horse Chestnut prefers humidity levels of 40–70%.

Well-draining loamy soil with added compost for nutrients. Good drainage is essential for Assam Horse Chestnut to prevent waterlogging, which leads to root rot and fungal issues.

Feed Assam Horse Chestnut every 6 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 loamy soil with added compost for nutrients. Avoid low spots where water collects after rain.

Assam Horse Chestnut is suited to USDA Zone 9b – 11b.

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.

Assam Horse Chestnut can spread to about 30 ft (9.1 m) and reach about 50 ft (15 m) tall. Space plants about 30 ft (9.1 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 Assam Horse Chestnut 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.

Assam Horse Chestnut is frost-tender (hardy to USDA zone 9). In colder areas grow it in a container and move it to a bright, frost-free place before the first frost.

Assam Horse Chestnut can be propagated through seeds. Similar propagation techniques also apply to california buckeye plant care, which shares the same genus.

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

Assam Horse Chestnut is susceptible to leaf miners, scale insects, horse chestnut scale. 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.

Assam Horse Chestnut grows outdoors in USDA Zone 9b – 11b. It survives winters down to planting zone 9b. Assam Horse Chestnut is native to warm temperate to subtropical areas of the eastern Himalayas from Sikkim through Bhutan and Assam to Arunachal Pradesh, and southwestern and southern China, Bangladesh, and mainland southeast Asia, except Cambodia and Peninsular Malaysia. In cooler regions, grow Assam Horse Chestnut as a houseplant or bring it indoors before the first frost.