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Flacourtia inermis


Flacourtia inermis Roxb.

Family Name: Salicaceae
Common Name: Rukam Masam, Batoko Plum, Lobi-lobi, Plum of Martinique, Thornless Rukam, Lobeh-lobeh


Family Name
Genus Epithet
Species Epithet
Name Authority
Name Status (botanical)
Common Names

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants) (Dicotyledon)
Plant Growth Form Tree (Medium (16m-30m), Small (6m-15m))
Lifespan (in Singapore) Perennial
Mode of Nutrition Autotrophic
Plant Shape Oval
Maximum Height 9 m to 15 m


Native Distribution Eastern Indonesia
Native Habitat Terrestrial (Primary Rainforest, Secondary Rainforest)
Preferred Climate Zone Tropical
Local Conservation Status Non-native (Spontaneous (Casual))

Description and Ethnobotany

Growth Form Small to medium-sized shrub or tree that grows to a height of 15 m.
Trunk Bark smooth, a mixture of light brown and light grey patches. The wood is hard and either orange red or red.
Foliage Leaves oval-shaped with serrate leaf margin (5 - 20 cm long, 2.5 - 9 cm wide). They have a spiral arrangement and tend to hang down from the branches. Young foliage is orange-red.
Flowers Clusters of 2 - 8 small, unscented flowers (3 - 5 mm in diameter) are located near the base of leaves and along the length of twigs, but not at the ends. The flowers have greenish yellow sepals, but no petals. This species is approximately free-flowering.
Fruit Fruits occur in clusters of 2 - 7 and each twig may hold more than 20 fruits. Round, shiny, cherry-like fruits (2 - 2.5 cm in diameter) are initially green, becoming red to reddish purple at maturity. Each fruit contains 4 - 14 small, stony seeds that have very sharp edges. Fruits have 4 - 5, small black-tipped projections arranged in a circle at the apex which are the remains of the styles. In Malaysia, trees bear fruits several times throughout the year with harvest most abundant during June and July. Each tree produces 40 - 100 kg fruit each year. Fruits ripen in about 3 - 5 months.
Others - Plant Morphology Landscaping: Trees are planted in parks and gardens for their attractive pinkish to red young foliage. Although the fruits are also an attractive red to reddish purple, the tree's prolific production of fruits that eventually drop to the ground in large numbers is sometimes a source of complaints. Unlike some of its relatives, this species is thornless and safe for passerbys.
Habitat Occurs in tropical rainforests.
Associated Fauna Phalanta phalantha phalantha (Leopard butterfly), Cupha erymanthis lotis (Rustic butterfly)
Cultivation This species grows best in full sun and moist, but well-drained soil. Mulch by adding organic compost or manure to the base of the tree. It grows poorly in waterlogged soils, but is able to grow on sandy soil. 
Etymology The genus “Flacourtia” is named after E. de Flacourt, former governor of Madagascar (1607 - 1660). The species epithet “inermis” is Latin for unarmed, referring to the absence of thorns on this plant. 
Ethnobotanical Uses Edible Plant Parts : Edible Fruits
Food (Fruit & Vegetable): This species is sometimes grown in Puerto Rico and the Virgin Islands for its fruit. Berries have a very sour, acidic taste and are used to make pies, syrups and jellies. It is sometimes combined with Kundangan to make chutney. They are usually not consumed raw due to its sour taste.
Medicinal: In traditional medicine, roots are used to prepare a poultice that is applied to wounds, sores, and sore throats. Leaf and root infusions are used to treat stomach distension.
Timber & Products: In Java, the wood is used to pound rice due to the hardness of the wood.

Landscaping Features

Landscaping It is suitable for planting along streetscapes, parks and gardens for its attractive young red leaves and fruits.
Desirable Plant Features Ornamental Foliage, Ornamental Fruits
Landscape Uses General, Roadside Tree / Palm, Parks & Gardens
Thematic Landscaping Butterfly Garden, Economic Garden, Naturalistic Garden

Fauna, Pollination and Dispersal

Fauna Pollination Dispersal Associated Fauna Caterpillar Food Plant (Leaves, Phalanta phalantha phalantha (Leopard butterfly), Cupha erymanthis lotis (Rustic butterfly) )
Pollination Method(s) Biotic (Fauna)
Seed or Spore Dispersal Biotic (Fauna)

Plant Care and Propagation

Light Preference Full Sun
Water Preference Moderate Water
Plant Growth Rate Moderate
Rootzone Tolerance Moist Soils, Well-Drained Soils, Fertile Loamy Soils
Pest(s) Chewing Insects
Propagation Method Seed, Grafting, Air-Layering


Foliage Retention Evergreen
Mature Foliage Colour(s) Green
Mature Foliage Texture(s) Smooth, Glossy / Shiny, Leathery
Prominent Young Flush Colour(s) Red
Foliar Type Simple / Unifoliate
Foliar Arrangement Along Stem Alternate
Foliar Attachment to Stem Petiolate
Foliar Shape(s) Non-Palm Foliage (Elliptical)
Foliar Venation Pinnate / Net
Foliar Margin Doubly Serrate
Leaf Area Index (LAI) for Green Plot Ratio 3.0 (Tree - Intermediate Canopy)

Non - Foliar and Storage

Trunk Type (Non Palm) Woody
Stem Type & Modification Woody
Root Type Underground (Tap Root, Fibrous Root)

Floral (Angiosperm)

Flower Colour(s) Cream / Off-White, Green
Flower Grouping Cluster / Inflorescence
Flower Location Axillary
Flowering Habit Polycarpic

Fruit, Seed and Spore

Mature Fruit Colour(s) Red
Fruit Classification Simple Fruit
Fruit Type Fleshy Fruit , Non-Accessory Fruit

Image Repository



Master ID 1627
Species ID 2920
Flora Disclaimer The information in this website has been compiled from reliable sources, such as reference works on medicinal plants. It is not a substitute for medical advice or treatment and NParks does not purport to provide any medical advice. Readers should always consult his/her physician before using or consuming a plant for medicinal purposes.
Species record last updated on: 07 October 2022.