Mimosa trees, commonly referring to species in the genera Albizia and Acacia (not true Mimosa, which are mostly herbaceous), are deciduous or evergreen trees and shrubs prized for their feathery foliage and vibrant, fluffy flowers. Native to regions including Asia, Australia, Africa, and the Americas, they belong to the Fabaceae (legume) family. Popular in gardens for their tropical aesthetic, they are often planted as ornamentals, though some species are invasive in certain areas, requiring careful consideration.
These trees typically grow 10–50 feet tall, with spreading, open, or umbrella-like canopies. Their foliage is usually bipinnate, featuring fern-like, compound leaves that fold at night (nyctinasty), giving a delicate, airy texture. Acacia species often have phyllodes (flattened leaf stalks) instead of true leaves, ranging from silvery-gray to bright green. Stems may be smooth or thorny, depending on the species.
Mimosa trees are renowned for their showy, spherical, or cylindrical flower clusters, blooming in late winter to summer. Flowers, typically 0.3–2 inches wide, are composed of numerous stamens, creating a fluffy, pom-pom-like appearance in shades of yellow, pink, or cream. They are highly attractive to pollinators like bees and butterflies, adding ecological value to gardens.
Most mimosa trees produce flat, elongated seed pods, 2–8 inches long, that turn brown or black when mature. These pods contain small, hard seeds and often persist on the tree, creating litter. Some species have pods used by wildlife, but they can contribute to invasiveness if seeds spread unchecked in favorable climates.
Mimosa trees thrive in full sun, preferring well-drained soils, from sandy to loamy, with moderate fertility. They are hardy in USDA Zones 6–11, depending on the species, with some tolerating light frost and others requiring tropical conditions. Regular watering is needed during establishment, but many are drought-tolerant once mature, making them suitable for xeriscaping in warm regions.
These trees are ideal for lawns, borders, or as focal points in sunny gardens, offering shade and visual interest. Their fast growth and attractive foliage suit coastal or arid landscapes, but their brittle wood requires protection from strong winds. Some species are invasive, particularly in warm, humid areas like the southeastern U.S. or Australia, so gardeners should monitor spread and remove seedlings to prevent ecological issues.
Mimosa Trees
Albizia julibrissin (Persian Silk Tree)
This deciduous tree, 20–40 feet tall with a 20–50-foot spread, forms a broad, umbrella-like canopy. Its fern-like, bipinnate leaves, 10–20 inches long, are bright green, folding at night. From May to July, fluffy, pink, pom-pom-like flowers, 1.5 inches wide, with silky stamens, bloom in clusters, attracting pollinators. Flat, 5–8-inch brown seed pods persist into winter. Hardy in Zones 6–9, it suits sunny lawns but is invasive in the southeastern U.S.
Albizia julibrissin ‘Rosea’ (Pink Silk Tree)
A smaller cultivar of A. julibrissin, growing 10–20 feet tall with a 15–25-foot spread, this deciduous tree has a compact, rounded canopy. Its bipinnate, fern-like leaves are medium green, 10–15 inches long. Vibrant, deep pink flower clusters, 1.5 inches across, bloom in summer, followed by 4–6-inch seed pods. More cold-tolerant (to -25°C), it’s ideal for smaller gardens or containers in Zones 6–9.
Albizia julibrissin ‘Summer Chocolate’
This striking cultivar, 15–20 feet tall and 15 feet wide, features a vase-shaped canopy. Its bipinnate leaves emerge green but turn deep burgundy to chocolate-brown, creating a dramatic backdrop. Pink, fluffy flowers, 1–1.5 inches wide, bloom from June to August, contrasting vividly with the foliage. Brown seed pods follow. Hardy in Zones 7–9, it’s perfect for adding bold color to sunny landscapes.
Albizia julibrissin ‘Ishii Weeping’
A weeping form, this deciduous tree grows 15–25 feet tall with a 20–30-foot spread, its drooping branches forming a cascading canopy. Its fern-like, bipinnate leaves, 10–20 inches long, are medium green. Pink, powder-puff flowers, 1.5 inches across, bloom in summer, followed by 5–7-inch seed pods. Hardy in Zones 6–9, it’s a focal point for gardens but requires space.
Acacia dealbata (Silver Wattle)
This evergreen tree, 30–50 feet tall with a 20–40-foot spread, has a rounded, open canopy. Its silvery-green, fern-like, bipinnate leaves, 4–6 inches long, shimmer in sunlight. Bright yellow, fragrant, spherical flower clusters (0.5 inches) bloom in late winter to early spring, creating a vibrant display. Flat, 2–4-inch seed pods follow. Hardy in Zones 8–10, it’s ideal for mild climates but can be invasive.
Acacia baileyana (Cootamundra Wattle)
A smaller evergreen, 20–30 feet tall with a 20–40-foot spread, this tree has a rounded, slightly weeping canopy. Its finely divided, silvery-blue bipinnate leaves, 2–3 inches long, give a soft texture. Clusters of golden-yellow, fluffy flowers, 0.3 inches wide, bloom profusely in late winter to spring, followed by 2–4-inch pods. Hardy in Zones 8–10, it suits sunny, coastal gardens.
Acacia pravissima (Ovens Wattle)
This evergreen, 15–25 feet tall with a 15–20-foot spread, forms a dense, triangular canopy. Its small, triangular, gray-green phyllodes (modified leaf stalks), 0.5 inches long, replace true leaves. Bright yellow, spherical flower heads, 0.2–0.3 inches, bloom in spring, followed by small, curved pods. Hardy in Zones 8–10, it’s excellent for hedges or screens in mild climates.
Acacia retinodes (Swamp Wattle)
Growing 15–30 feet tall with a 15–25-foot spread, this evergreen has a rounded, open canopy. Its narrow, lance-shaped phyllodes, 2–6 inches long, are bright green. Small, yellow, ball-shaped flowers, 0.3 inches wide, bloom intermittently year-round in warm climates, followed by slender, 3–6-inch pods. Hardy in Zones 8–11, it’s suited for wetter soils in sunny gardens.
Acacia farnesiana (Sweet Acacia)
This deciduous to semi-evergreen shrub or small tree, 15–25 feet tall with a 15–20-foot spread, has a rounded, thorny canopy. Its bipinnate, fern-like leaves, 2–3 inches long, are light green. Fragrant, golden-yellow, pom-pom flowers, 0.5 inches wide, bloom in spring, followed by 2–3-inch cylindrical pods. Hardy in Zones 8–11, it’s ideal for xeriscaping or as a non-invasive mimosa alternative.
Albizia julibrissin ‘Ombrella’
This deciduous cultivar, growing 20–30 feet tall with a 25–35-foot spread, forms a wide, umbrella-shaped canopy. Its bipinnate, fern-like leaves, 12–18 inches long, are bright green, folding at night. Vivid pink, fluffy flower heads, 1.5–2 inches wide, bloom profusely from June to August, followed by 5–7-inch brown seed pods. Hardy in Zones 6–9, it’s a striking choice for sunny lawns, though potentially invasive in the southeastern U.S.
Acacia podalyriifolia (Pearl Acacia)
This evergreen small tree or shrub, 10–20 feet tall with a 10–15-foot spread, has a rounded, compact canopy. Its silvery-gray, oval phyllodes, 1–2 inches long, give a soft, shimmering effect. Bright yellow, spherical flower clusters, 0.5 inches wide, bloom in winter to early spring, followed by 2–4-inch pods. Hardy in Zones 9–11, it’s ideal for coastal gardens or as a low hedge.
Acacia saligna (Golden Wreath Wattle)
A fast-growing, evergreen tree or shrub, 15–30 feet tall with a 10–20-foot spread, featuring a weeping, open canopy. Its lance-shaped, dark green phyllodes, 3–6 inches long, are slightly curved. Golden-yellow, ball-shaped flowers, 0.3 inches wide, bloom in early spring, followed by slender, 3–5-inch pods. Hardy in Zones 8–10, it suits dry, sunny sites but can be invasive in some areas.
Acacia cultriformis (Knife-Leaf Wattle)
This evergreen shrub or small tree, 10–15 feet tall and wide, has a dense, rounded canopy. Its triangular, silver-gray phyllodes, 0.5–1 inch long, resemble small knives. Bright yellow, cylindrical flower clusters, 1–2 inches long, bloom in spring, followed by 2–3-inch pods. Hardy in Zones 9–11, it’s perfect for low-maintenance hedges or rock gardens in warm climates.
Acacia longifolia (Sydney Golden Wattle)
Growing 15–25 feet tall with a 15–20-foot spread, this evergreen has a spreading, bushy canopy. Its long, narrow, bright green phyllodes, 3–6 inches long, are leathery. Golden-yellow, spike-like flower clusters, 2–4 inches long, bloom in late winter to spring, followed by 3–5-inch pods. Hardy in Zones 8–10, it’s suited for coastal or erosion-control plantings but may be invasive.
Acacia verticillata (Prickly Moses)
This evergreen shrub or small tree, 6–20 feet tall with a 10–15-foot spread, has a dense, spreading form. Its needle-like, dark green phyllodes, 0.5–1 inch long, grow in whorls. Pale yellow, cylindrical flower spikes, 1–2 inches long, bloom in spring, followed by small, curved pods. Hardy in Zones 8–10, it’s ideal for hedges or windbreaks in mild climates.
Acacia aneura (Mulga)
A tough, evergreen tree, 15–25 feet tall with a 10–20-foot spread, forming a dense, rounded canopy. Its narrow, silver-gray phyllodes, 1–3 inches long, are sickle-shaped. Sparse, yellow, rod-like flower spikes, 1–2 inches long, bloom intermittently, followed by flat, 1–2-inch pods. Hardy in Zones 8–11, it’s perfect for arid, sunny gardens or xeriscaping.
Acacia boormanii (Snowy River Wattle)
This evergreen shrub or small tree, 10–15 feet tall with a 10–12-foot spread, has an upright, bushy form. Its fine, needle-like, bright green phyllodes, 1–2 inches long, give a soft texture. Profuse, pale yellow, ball-shaped flowers, 0.3 inches wide, bloom in late winter to spring, followed by 2–3-inch pods. Hardy in Zones 8–10, it’s great for screens or small gardens.
Acacia spectabilis (Mudgee Wattle)
A deciduous to semi-evergreen tree, 10–20 feet tall with a 10–15-foot spread, featuring a rounded canopy. Its bipinnate, fern-like leaves, 4–6 inches long, are bright green. Bright yellow, fluffy flower balls, 0.5 inches wide, bloom in late winter to spring, followed by 2–4-inch pods. Hardy in Zones 8–10, it’s a vibrant choice for sunny borders.
Acacia floribunda (White Sallow Wattle)
This evergreen tree or shrub, 15–25 feet tall with a 10–20-foot spread, has a weeping, open canopy. Its narrow, lance-shaped phyllodes, 2–4 inches long, are bright green. Creamy-yellow, cylindrical flower spikes, 1–2 inches long, bloom in spring, followed by 2–4-inch pods. Hardy in Zones 8–10, it’s ideal for informal hedges or coastal gardens.
Acacia cognata (River Wattle)
A small, evergreen tree or shrub, 10–20 feet tall with a 10–15-foot spread, with a weeping, dome-shaped canopy. Its narrow, willow-like, bright green phyllodes, 2–4 inches long, create a soft look. Pale yellow, ball-shaped flowers, 0.3 inches wide, bloom in spring, followed by small pods. Hardy in Zones 9–11, it’s perfect for containers or small, sunny spaces.