Silver Wattle Plant Care

Silver Wattle (Acacia dealbata) belongs to the Fabaceae family within the Acacia genus. Silver Wattle is native to south-eastern mainland Australia. Silver Wattle is also known as Mimosa, Blue Wattle, Sydney Wattle.

Silver Wattle displays a tall, spreading tree growth habit, reaching up to 30 ft tall with a spread of approximately 20 ft. Silver Wattle produces clusters of small yellow or white flowers.

Leaf size: approximately 4 inches.

Water a young or newly planted Silver Wattle 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.

Silver Wattle thrives in full sun.

Acacia dealbata tolerates temperatures of 50–90°F. Silver Wattle prefers humidity levels of 40–70%.

Well-draining sandy soil mix with some organic matter. Good drainage is essential for Silver Wattle to prevent waterlogging, which leads to root rot and fungal issues.

Feed Silver Wattle 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 mix with some organic matter. Avoid low spots where water collects after rain.

Silver Wattle is suited to USDA Zone 8a – 10b.

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.

Silver Wattle can spread to about 20 ft (6.1 m) and reach about 30 ft (9 m) tall. Space plants about 20 ft (6.1 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 Silver Wattle 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.

Silver Wattle is hardy down to USDA zone 8a, so once established it can stay outdoors through winter in that zone and warmer ones.

Water deeply in late autumn before the ground freezes, and spread a 5–8 cm (2–3 in) layer of mulch over the root zone, keeping it away from the trunk.

Young and container-grown trees need extra protection: roots in a pot freeze much more easily than roots in the ground.

Silver Wattle can be propagated through seeds, cuttings. Similar propagation techniques also apply to gold dust wattle plant care, which shares the same genus.

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

Silver Wattle 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.

Silver Wattle grows outdoors in USDA Zone 8a – 10b. It survives winters down to planting zone 8a. Silver Wattle is native to south-eastern mainland Australia.