The Finger Lime was formerly known as Microcitrus australasica but has undergone botanical revision and has been reunited with the genus Citrus. Details of the revision are in:
Mabberley, D. (1998). Australian Citreae with notes on other Aurantioideae (Rutaceae), Telopea 7(4), 1998.
Citrus australasica is a medium to large shrub or small tree. The small leaves are oval shaped and up to 40 mm long on thorny stems. Flowers are 10 – 14 mm in diameter, white or pale pink in colour and appear in late summer and autumn. The flowers are followed by elongated fruits about 30-120 mm long by 10-15 mm wide. The fruits ripen in winter through to spring and may be green, yellow, black, purple or red. The pulp is green, yellow or pink. The fruits are edible and have a strong citrus flavour which is widely sought by “bush tucker” enthusiasts.
Finger lime is receiving considerable attention as a commercial food plant and research is being carried out to develop selected, superior forms of the species and also to develop hybrids with exotic Citrus species. A recently developed cultivar of C.australasica known as “Rainforest Pearl” is becoming available through specialist nurseries and is claimed to be a vigorous grower bearing pink/green fruit with a pink pulp. Another recent cultivar is the “Blood Lime”, a cross between a mandarin and a finger lime and characterised by its blood red rind, flesh and juice.
In cultivation, C.australasica is hardy in tropical to temperate climates in well drained conditions. Plants are usually slow growing and seedlings may take from 5 to 15 years to reach maturity.
Propagation is possible from seed but germination can be erratic. Plants can also be grown from cuttings but these are slow to strike and usually produce well below 50% success rate. Commercially, plants are propagated by grafting or budding onto other Citrus rootstocks.
Citrus australasica: Flowers
Photo: Tony Rodd
Citrus australasica: A finger lime fruit split
to show the pulp and seeds
Photos: Tony Rodd