Delta Grevillea Plant Care

Delta Grevillea (Grevillea delta) belongs to the Proteaceae family within the Grevillea genus. Delta Grevillea is native to restricted area in the south-west of Western Australia. Delta Grevillea is also known as Delta Spider Flower.

Delta Grevillea displays an upright, bushy shrub growth habit, reaching up to 6 ft tall with a spread of approximately 4 ft. Delta Grevillea produces showy clusters of red, pink, or white flowers.

Leaf size: approximately 4 inches.

Water a young or newly planted Delta Grevillea 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.

Delta Grevillea thrives in full sun to partial shade.

Grevillea delta tolerates temperatures of 50–80°F. Delta Grevillea prefers humidity levels of 40–70%.

Well-draining sandy loam with added organic matter. Good drainage is essential for Delta Grevillea to prevent waterlogging, which leads to root rot and fungal issues.

Feed Delta Grevillea 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 loam with added organic matter. Avoid low spots where water collects after rain.

Delta Grevillea 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.

Delta Grevillea can spread to about 4 ft (1.2 m) and reach about 6 ft (2 m) tall. Space plants about 4 ft (1.2 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 Delta Grevillea 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.

Delta Grevillea 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.

Delta Grevillea can be propagated through seeds, cuttings. Similar propagation techniques also apply to acacia grevillea plant care, which shares the same genus.

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

Delta Grevillea 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.

Delta Grevillea grows outdoors in USDA Zone 12a. It survives winters down to planting zone 12a. Delta Grevillea is native to restricted area in the south-west of Western Australia. In cooler regions, grow Delta Grevillea as a houseplant or bring it indoors before the first frost.