Acacia baileyana

The Acacia baileyana, also known as Bailey's Mimosa, is an Australian species relatively unknown among gardeners despite its exceptional ornamental qualities, easy cultivation, and good cold resistance, down to -8°C. It is a small evergreen tree with long flexible branches adorned with finely cut blue-grey foliage. Its bright yellow flowering is abundant in late winter or early spring. The shrub adapts to mediocre soils, tolerates drought well, and does not sucker. A true star in the garden or on the terrace!

The mimosas should not be confused with the tree we call acacia, which belongs to the botanical genus Robinia. They belong to the fabaceae family, just like alfalfa and lupins. The Acacia baileyana is a shrub native to Tasmania and Australia, specifically the southern part of New South Wales. It is most often grafted onto Acacia rootstock (the four seasons mimosa) which has the advantage of not suckering and allows for cultivation in limestone and very dry soils. When grown on its own roots, this mimosa dislikes excessive limestone. With a supple, rounded habit carried by long slightly drooping branches, it reaches about 4m (13 in 1 ft) in all directions at maturity. Its growth is rapid, already exceeding 2m (6 in 7 ft) in height at 2 years, in a Mediterranean climate. Its lifespan is about 10 to 15 years. The bark is the same blue-grey tone as the mature foliage. The numerous flower buds appear from late summer on the branches. Flowering occurs from January to March depending on the climate and weather conditions, and lasts about 3 weeks. The small round flowers are bright yellow and grouped in clusters in the axils of the leaves located towards the tips of the branches. Their scent is light, more noticeable during the hottest hours of the day. The foliage of Bailey's mimosa consists of small finely cut leaves with tiny blue-grey leaflets. The shrub itself can withstand short freezes around -8/-10°C (17.6 - 14°F), but the less hardy rootstock will perish below -5°C (23°F) if not protected. Since the root system is quite shallow, it is advisable to plant this mimosa in a sheltered location away from strong winds.

When planted in the ground in mild climates, Bailey's Mimosa can be placed as a solitary specimen, sheltered from strong winds, or in a shrub bed. It can be paired with other tender shrubs with an exotic appearance, such as Caesalpinia gilliesii, Sesbania punicea, escallonias, or even evergreen ceanothus. It can be grown in a pot and protected from winter frosts in a minimally heated greenhouse or conservatory.