Humboldt Oak Plant Care

Humboldt Oak (Quercus humboldtii) belongs to the Fagaceae family within the Quercus genus. Humboldt Oak is native to Colombia, Panamanian Darién. Humboldt Oak is also known as Colombian Oak, Andean oak, Roble.

Humboldt Oak displays a slow, upright growth habit, reaching up to 100 ft tall with a spread of approximately 60 ft. Humboldt Oak produces inconspicuous catkins.

Leaf size: approximately 5 inches.

Water a young or newly planted Humboldt Oak 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.

Humboldt Oak thrives in full sun.

Quercus humboldtii tolerates temperatures of 45–85°F. Humboldt Oak prefers humidity levels of 40–70%.

Well-draining. Good drainage is essential for Humboldt Oak to prevent waterlogging, which leads to root rot and fungal issues.

Feed Humboldt Oak every 2 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. Avoid low spots where water collects after rain.

Humboldt Oak is suited to USDA Zone 9b – 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.

Humboldt Oak can spread to about 60 ft (18.3 m) and reach about 100 ft (30 m) tall. Space plants about 60 ft (18.3 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 Humboldt Oak 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.

Humboldt Oak 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.

Humboldt Oak can be propagated through by seeds or cuttings. Similar propagation techniques also apply to white oak plant care, which shares the same genus.

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Humboldt Oak is susceptible to oak leaf blister, oak wilt, gypsy moth. 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.

Humboldt Oak grows outdoors in USDA Zone 9b – 12a. It survives winters down to planting zone 9b. Humboldt Oak is native to Colombia, Panamanian Darién. In cooler regions, grow Humboldt Oak as a houseplant or bring it indoors before the first frost.