Common name: Limeberry

Limeberry is an ornamental and fruiting shrub native to Southeast Asia, with a natural range spanning parts of southern China, Vietnam, Thailand, Malaysia, and the Philippines.

It has a multi-stemmed, wide-branching habit and can reach up to 7 m (23 ft), though it is typically 2 to 3 m (7 to 10 ft) tall and grows slowly to moderately, depending on growing conditions. The branches are armed with sharp needle-like spines up to 1.6 cm (0.6 in) long, arising in pairs from the base of the leaves. 

The leaves are trifoliate, consisting of three dark, glossy green oval leaflets, with the middle leaflet up to 4 cm (1.6 in) long and twice the size of the other two. They have a resinous, citrusy aroma when crushed and remain on the plant year-round.

The flowers are small, three-petaled, white, and sweetly fragrant, with an orange-blossom scent. They bloom intermittently throughout the year, but are most abundant in summer. 

Fertilised flowers develop into small oval fruits up to 1.5 cm (0.6 in) long, with thick, dimpled green peel that turns red to purple-red when ripe. The pulp is jelly-like and bittersweet, with a citrus marmalade flavour, and surrounds a single seed, though occasionally two or three seeds. 

Edible uses

Fruit in syrup or juice - The fruit is edible but too bitter and astringent to eat fresh, and is more usually preserved in syrup...

Candied fruit - ...candied...

Dried fruit - ...dried...

Fruit spread - ...made into jam or marmalade...

Syrup or cordial - ...or made into a fruit syrup or cordial.

Pickled fruit - People also commonly pickle it in southern and western India.

Environmental uses

Hedge plant - People cultivate it as a garden hedge because it has a low-branching habit, deep green foliage, and fragrant flowers...

Barrier plant - ...and as a barrier plant on account of its sharp spines.

Bonsai plant - The plant's small leaves also make it a suitable candidate for bonsai culture.

Seaside garden plant - Limeberry is particularly well-suited to seaside gardens because it tolerates salt spray.

Material uses

Tool handles - Although the stems are small in diameter, the wood is hard and durable and is reportedly used to make tool handles.

Firewood - It also makes excellent firewood...

Charcoal - ...and charcoal.

Climate

Grows naturally in moderately humid subtropical and tropical lowland to mid-elevation climates, generally in frost-free areas with annual lows of 16 to 25°C, annual highs of 25 to 35°C, annual rainfall of 600 to 2000 mm and a dry season of 8 months or less.

Growing

New plants are usually grown from seed, though cuttings are also an option. It performs best in rich, free-draining clay, loam, and sand soils that are moderately acidic to alkaline (pH 5.0 to 8.0), with full to partial sun exposure. It is intolerant of poorly draining or waterlogged soils.

Problem features

Birds eat the fruit and disperse the seed. Once established, it re-seeds naturally, forming dense thickets.

It is recorded as an invasive species on the island of Reunion in the Indian Ocean and in the eastern Caribbean on the islands of Guadeloupe, Martinique and St Martin. It also suckers freely from the roots, which contributes to its weediness. The Hawaii Pacific Weed Risk Assessment project (HPWRA) assessed it as a high weed risk species for Hawaii. 

The branches are armed with sharp spines that can inflict injury on the unwary.

Books

• Adams, C. D. 1972, Flowering plants of Jamaica, University of the West Indies, Mona, Greater Kingston

• Bannochie, Iris, 1993. Gardening in the Caribbean. 1 Edition. Macmillan.

• Brown, William Henry. 1920, Minor products of Philippine forests, Bureau of Printing, Manila

• Chaplin, L. T. & Brandies M. M. 1998, The Florida Gardener's Book of Lists, Taylor Publishing Company, Dallas, Texas

• Clay, H. et al. 1987, Tropical shrubs, University Press of Hawaii, Honolulu

• Genders, R. 1978, Scented flora of the world, Robert Hale Publishing, London & St. Martin's Press, New York

• Kennard, W. C. & Winters, H. F. 1960, Some fruits and nuts for the tropics, Miscellaneous Publication No. 801, U.S. Department of Agriculture, Federal Experimental Station, Mayaguez, Puerto Rico

• Little, E. L. 1974, Trees of Puerto Rico and the Virgin Islands, Vol. 2, United States Department of Agriculture (USDA), Washington D.C.

• Macmillan, H. F. 1943, Tropical planting and gardening : with special reference to Ceylon, 5th ed, Macmillan Publishing, London

• Martin, F. M., et al. 1987, Perennial edible fruits of the tropics : an inventory, U.S. Dept. of Agriculture (USDA), Agricultural Research Service, U.S. Government Printing Office (GPO), Washington, D.C.

• Randall, R. P. 2007, The introduced flora of Australia and its weed status, Cooperative Research Centre for Australian Weed Management, Glen Osmond, South Australia

• Roecklein, J. C & Leung, P.S. 1987, A Profile of economic plants, Transaction Books, New Brunswick, New Jersey

• Seidemann, J. 2005, World spice plants: economic usage botany taxonomy, Springer-Verlag, Berlin

• Standley, P. C. 1920, Trees and shrubs of Mexico, Government Printing Office (GPO), Washington D.C.

Articles, Journals, Reports and Working Papers

• Dagar, J. C. & Singh, G. 2007, Biodiversity of Saline and Waterlogged Environments: Documentation, Utilization and Management, NBA Scientific Bulletin, (9), 78.

• Morton, J. F. 1976, Pestiferous spread of many ornamental and fruit species in south Florida. In Proceedings of the Florida State Horticultural Society (Vol. 89, pp. 348-353).