Sweet acacia (Acacia farnesiana)
At a glance
- Lifecycle
- Perennial (hardy)
- Exposure
- Full sun
- Frost limit
- −12.2 °C
Cultivation
Prefers a light sandy loam and a very sunny position sheltered from strong winds. Whilst this species is not very tolerant of cold, being damaged by even a few degrees of frost, the variety A. farnesiana cavenia seems to be more resistant to both drought and frost. Both A. farnesiana and its var. cavenia are extensively cultivated for the essential oil in their flowers in and around Cannes, southern France, which is the centre for production of the perfume[229, 269. A good bee plant. This species has a symbiotic relationship with certain soil bacteria, these bacteria form nodules on the roots and fix atmospheric nitrogen. Some of this nitrogen is utilized by the growing plant but some can also be used by other plants growing nearby.
Propagation
Seed - best sown as soon as it is ripe in a sunny position in a warm greenhouse. As soon as the seedlings are large enough to handle, prick them out into individual pots and grow them on in a sunny position in the greenhouse for their first winter. Plant them out in late spring or early summer, after the last expected frosts, and consider giving them some protection from the cold for their first winter outdoors. Cuttings of half-ripe wood with a heel, July/August in individual pots in a frame.
Edible uses
A low-quality gum obtained from the plant is used to prepare sweets.
Medicinal uses
The bark is astringent and demulcent. The gummy roots have been chewed as a treatment for sore throat. A decoction of the gum from the trunk has been used in the treatment of diarrhoea. An infusion of the flowers has been used as a stomachic. It is also used in the treatment of dyspepsia and neuroses. The powdered dried leaves have been applied externally as a treatment for wounds. The green pods have been decocted and used in the treatment of dysentery and inflammations of the skin and raucous membranes. The juice of the bark is used in Nepal to treat swellings.
Material uses
An essential oil called Cassie is distilled from the flowers. The bark and the fruit are a source of tannin and used in making dyes and inks. A gummy substance obtained from the young pods is used to mend pottery. A mucilage can be manufactured from the gummy sap. The woody branches are used in India as tooth brushes. In suitable climates the plant is grown as a hedge. Wood - heavy, hard, durable in the soil, close-grained. Used for fencing posts, agricultural implements, pegs, woodenware etc.
Habitat
Dry sandy soils in pinelands, hammocks and disturbed areas in south-eastern N. America.
Native range
The original range is uncertain, but is probably tropical America.
Scientific synonyms Vachellia farnesiana