Idiots Plum Plant Care

Idiots Plum (Idiospermum australiense) belongs to the Calycanthaceae family within the Idiospermum genus. Idiots Plum is also known as Green Dinosaur.

Idiots Plum displays a tall canopy tree growth habit, reaching up to 50 ft tall with a spread of approximately 30 ft. Idiots Plum produces large, showy red flowers with a unique fragrance.

Leaf size: approximately 10 inches.

Water a young or newly planted Idiots Plum 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.

Idiots Plum thrives in partial shade to full sun.

Idiospermum australiense tolerates temperatures of 60–80°F. Idiots Plum prefers humidity levels of 60–80%. A pebble tray or humidifier helps maintain adequate moisture around the plant.

Rich, well-draining soil with high organic content. Good drainage is essential for Idiots Plum to prevent waterlogging, which leads to root rot and fungal issues.

Feed Idiots Plum 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 partial shade to full sun and rich, well-draining soil with high organic content. Avoid low spots where water collects after rain.

Idiots Plum 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.

Idiots Plum 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 Idiots Plum 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.

Idiots Plum 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.

Idiots Plum can be propagated through seeds, stem cuttings.

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

Idiots Plum is susceptible to aphids, scale insects, spider mites. 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.

Idiots Plum grows outdoors in USDA Zone 13a. It survives winters down to planting zone 13a. In cooler regions, grow Idiots Plum as a houseplant or bring it indoors before the first frost.