Acacia longifolia subp. sophorae | ‘Coastal Wattle’, ‘Sydney Golden Wattle’ | 25 seeds
We’re pleased to offer this great Acacia longifolia subsp. sophorae seed (syn. Acacia sophorae, Racosperma longifolium subsp. sophorae), all the way from Australia! Start some truly magnificent trees for your garden…
Most often known as the ‘Coastal Wattle’ or ‘Sydney Golden Wattle’, longifolia is also known under many other names, including ‘Acacia à Longues Feuilles’, ‘Acacia Trinervis’, ‘Acácia-de-Espigas’, ‘Acácia-de-Folhas-Longas’, ‘Aroma Doble’, ‘Gaggia a Foglie Lunghe’, ‘Golden Rods’, ‘Golden Wattle’, ‘Kätzchen’, ‘Langblaarwattel’, ‘Langblättrige’, ‘Long-leaved Acacia’, ‘Mimosa Chenille’, ‘Mimosa de Flores Amarelas’, ‘Sallow Wattle’, ‘Swallow Acacia’, ‘Sydney Acacia’ and ‘White Sallow’. Originating from Australia, it’s a popular and fast-growing perennial shrub or tree of the Fabaceae family.
Two subspecies are described within Acacia longifolia; subsp. longifolia and subsp. sophorae (however, many people consider them to be distinct species, Acacia longifolia and Acacia sophorae). As a general rule of thumb, mature sophorae is roughly half the size of longifolia and forms thicker (but more brittle) phyllodes and noticeably more irregularly-shaped seedpods. The species is close relative of Acacia floribunda and Acacia maidenii.
Growing as a spreading shrub or small erect tree, Acacia longifolia ranges from two to ten metres tall by two to twenty metres wide. As with of its relatives among the Acacia, rather than leaves the plant sports smoothly pliable, linear to elliptic phyllodes (flattened leaf stalks), between five and twenty-five centimetres long and ten to thirty millimetres wide. Longifolia’s wonderfully-scented, lemon-yellow flowers are two to five centimetres long and are followed by cylindrical or semi-cylindrical seedpods. The seedpods are five to fifteen centimetres long and five to ten millimetres wide and can produce anything up to around eleven thousand seeds each year. Seed dispersal is mainly caused by ants, birds, rodents, soil and water, while pollination is taken care of by bees and other insects, such as Apis mellifera.
In common with many other Acacia, longifolia and its products have many practical and economic applications. These include use in agroforestry and revegetation, as charcoal and fuel wood, as cut flowers, as dyestuffs and tanning agents, for erosion control and dune stabilisation, as food source (Acacia seeds have a low glycaemic index, containing approximately 26% protein, 26% available carbohydrate, 32% fibre and 9% fat), for grafting stock, as timber, for its gum, as nitrogen-fixer and as an ornamental or landscaping tree. It’s also recommended (along with the closely-related species Acacia melanoxylon) for use as a cheap replacement compost to pine bark, in combination with other organic materials, such as peat moss.
Growing naturally in full sun in USDA Climate Zones 10 and 11, longifolia’s preferred habitats are sandy coasts and dunes, but it also thrives across agricultural and bush land, forests, rail culverts and roadsides, riparian zones, riverine areas and scrub and grassland. It’s also both drought and saline-resistant, capable of growing in nutrient-poor media and well-adapted to fire.
Longifolia is an easy tree to grow from seed and viability remains high (roughly ninety percent) even after years of storage. Illustrating this longevity, some tests demonstrated 12% germination after “fifty years of open storage at room temperature”! Suitable pre-treatment (soaking or scarification – see our Cultivation section for more details) and a warm climate offer the best chances, greatly increasing the germination rate of this fantastic Wattle. It does best on light well-drained sandy loam, whether acid, neutral or basic, but can’t tolerate strong shade or wind. The mean annual temperature should be between 10ºC and 25ºC; 10ºC to 19ºC is ideal.
A fast-growing and low-maintenance species, it’s known as the ‘Golden Wattle’ for good reason, so why not sow some great Acacia longifolia subsp. sophorae seed today!
All the seed sold by Arkham’s Botanical was freshly and ethically sourced in 2018