The weeping acacia or Weeping Myall, scientifically known as Acacia pendula, is a species within the Fabaceae family, specifically in the subfamily Mimosoideae, which includes many wattles native to Australia. The genus Acacia encompasses over 1,000 species, predominantly shrubs and trees, with A. pendula distinguished for its graceful form. Its scientific name derives from Latin, with “pendula” meaning “hanging down,” reflecting its drooping branches. Initially described by George Don in 1832, it was briefly reclassified as Racosperma pendulum before returning to Acacia in 2014. As a legume, it shares the family’s trait of nitrogen-fixing root nodules, enhancing soil fertility in its arid habitats.
Acacia pendula is a small, evergreen tree or shrub, typically growing 16–33 feet (5–10 meters) tall and 13–20 feet (4–6 meters) wide, with a weeping, pendulous habit. Its bark is hard, fissured, and dark gray to black, contrasting with slender, silvery-gray to blue-green phyllodes (modified leaf-like structures) that are narrowly elliptic, 1.6–5.5 inches (4–14 cm) long, and 0.12–0.39 inches (3–10 mm) wide, often curved with fine, indistinct veins. In spring or irregularly throughout the year, it produces small, pale yellow, globular flower heads in short racemes, which are subtle but attract pollinators like bees. Flat, leathery pods, 1.6–3.1 inches (4–8 cm) long, contain seeds favored by birds. Its slow growth and silvery foliage give it a ghostly, elegant appearance.
Native to Australia, the Weeping Myall is found primarily west of the Great Dividing Range, from central Queensland through New South Wales to northern Victoria, with isolated populations in far eastern South Australia. It thrives in dry outback regions, often on floodplains, riverbanks, and woodlands, favoring alluvial soils of clay, sand, or silt with 16–24 inches (400–600 mm) of annual rainfall. In New South Wales, it has a disjunct distribution, sometimes dominating clay-heavy woodlands. Due to its striking foliage, it’s cultivated beyond Australia in arid regions like Iran and Kuwait, though it remains most common in its native inland habitats, where it supports local wildlife.
Acacia pendula is hardy in USDA zones 8a–11, tolerating temperatures as low as 15°F (-9°C) for short periods, making it frost-tolerant compared to many wattles. It thrives in warm, arid climates with temperatures between 50°F and 100°F (10°C–38°C), ideal for desert and Mediterranean regions. In zones 8a–8b, it may experience leaf damage in severe cold but typically recovers. In colder zones (below 8a), it can be grown in containers and brought indoors during winter, requiring bright light and minimal water to survive cooler months.
The Weeping Myall is prized in landscaping for its graceful, weeping form and silvery foliage, making it a standout in xeriscapes, native gardens, and urban settings. Its drought tolerance and low water needs suit water-wise designs, where it serves as a specimen tree, street tree, or windbreak. Planted singly, it enhances patios, courtyards, or entryways; in groups, it creates shade or screens for privacy. Its nitrogen-fixing roots improve soil, benefiting nearby plants, while its seeds attract birds like parrots, boosting biodiversity. The tree’s low litter and tolerance for clay or poor soils make it practical, though its tendency to sucker may require management in confined spaces.
How To Grow And Care For Weeping Acacia (Acacia pendula)
Cultivating the Weeping Myall (Acacia pendula) is rewarding for its graceful, silvery foliage and drought tolerance.
Light Requirements
Provide full sun, with at least 6–8 hours of direct sunlight daily, to ensure robust growth and vibrant phyllode color. Weeping Myall thrives in open, sunny locations typical of its outback habitat. Partial shade reduces vigor and may cause sparse foliage, so prioritize unshaded sites for best results.
Soil Preferences
Plant in well-draining soil, preferably clay, loam, or sandy loam, with a pH of 6.0–7.5. It tolerates poor, nutrient-deficient soils but benefits from slight organic matter at planting. Avoid waterlogged conditions, as excess moisture causes root rot; incorporate sand or gravel in heavy soils to improve drainage.
Watering Needs
Water regularly during the first year to establish roots, providing 1–2 inches (2.5–5 cm) weekly. Once established, water every 3–4 weeks in summer, allowing soil to dry between waterings, and reduce or stop in winter. Its drought tolerance makes overwatering a risk, so monitor for soggy soil to prevent root issues.
Temperature Range
Grow in USDA zones 8a–11, where temperatures range from 15°F to 100°F (-9°C to 38°C). It handles brief frosts but may lose phyllodes in zones 8a–8b during severe cold, regrowing in spring. In colder zones, cultivate in pots and move indoors during winter, keeping above 50°F (10°C) with minimal water.
Humidity Levels
Weeping Myall prefers low to moderate humidity (20–50%), suited to arid climates. High humidity can encourage fungal diseases, so ensure good air circulation, especially in dense plantings. Indoor plants need dry conditions in winter; avoid misting to prevent phyllode or stem issues.
Container Selection
Choose pots with drainage holes to prevent water buildup. Terracotta or plastic pots work well, at least 18–24 inches (45–60 cm) wide to support the tree’s root system. Use a pot heavy enough to stabilize its weeping form, repotting every 2–3 years to refresh soil and accommodate slow growth.
Fertilization
Apply a low-phosphorus, slow-release fertilizer (e.g., 10-5-10 NPK) once in early spring to support growth, as high phosphorus harms native acacias. Alternatively, use diluted liquid fertilizer monthly during spring–summer. Avoid over-fertilizing, as excess nutrients cause weak, leggy growth or reduced drought tolerance.
Pruning
Prune lightly in late winter or early spring to shape the canopy, remove dead branches, or control suckering at the base. Cut just above a node with clean shears to avoid disease. Minimal pruning preserves its natural weeping form; heavy cuts may stress the slow-growing tree and delay recovery.
Propagation
Propagate via seeds or cuttings. Soak seeds in hot water (180°F/80°C, then cool) for 24 hours, sowing in a sandy mix; germination takes 2–6 weeks at 70–80°F (21–27°C). Hardwood cuttings, taken in spring, root in 6–8 weeks with rooting hormone. Both methods require patience due to slow early growth.
Pest Control
Watch for pests like scale insects, aphids, or borers, which may target stressed trees. Inspect phyllodes and bark regularly, treating infestations with neem oil or insecticidal soap in early morning. Maintain proper watering and avoid wounding the bark to reduce pest susceptibility, as healthy trees resist better.
Repotting
Repot container-grown trees every 2–3 years in spring, or when roots crowd the pot. Gently remove, trim dead roots, and replant in fresh, well-draining mix at the same depth. Water sparingly after repotting and provide shade for a week to ease stress, ensuring the new pot has ample drainage.
Winter Care
In zones 8a–8b, protect from frost by mulching the base with 2–3 inches (5–7.5 cm) of bark or straw and covering with frost cloth during freezes. If phyllodes drop, wait until spring to prune dead growth, as roots often survive. Indoor plants need bright light, cool temperatures (50–60°F/10–16°C), and minimal water in winter.
Common Issues
Address overwatering (yellowing phyllodes, root rot) by improving drainage and reducing frequency. Underwatering (wilting, leaf drop) requires slight watering increases. Suckering can be managed by removing shoots at the base. Poor growth in shade indicates a need for more sun; relocate or thin nearby plants to boost light exposure.