Singapore Government Logo

A Singapore Government Agency Website

Coix lacryma-jobi

Back

Coix lacryma-jobi

Family Name: Poaceae (Gramineae)
Synonyms: Coix lacryma, Acroceras lacryma, Coix exaltata, Coix ovata, Coix pendula, Coix arundinacea, Coix agrestis, Acroceras lacryma-jobi
Common Name: Job's Tears, Gromwell Reed, Pearl Barley, Corn Bead, Coix Millet, 川谷, 野米仁, 野薏仁, 野薏米

Named after its tear-drop shaped seeds, the Job’s Tears plant (Coix lacryma-jobi) is a member of the grass family, with many uses. After the removal of the hard husk, the seeds can be cooked into chewy grains, made into barley tea, or used in Traditional Chinese Medicine. Dried seeds can also be strung into ornamental accessories.

Name

Family Name
Genus Epithet
Species Epithet
Name Status (botanical)
Synonyms
Common Names
Comments
Species Summary

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants)
Plant Growth Form Shrub
Mode of Nutrition Autotrophic
Maximum Height 0.9 m to 1.8 m

Biogeography

Native Distribution Tropical Asia

Description and Ethnobotany

Growth Form Perennial grass in tropical or subtropical environments. 
Foliage Leaves are linear or lanceolate with an entire leaf margin and a pointed apex (1.5 - 4 cm wide, 20 - 50 cm long). This species is a monocotyledon, so it lacks petioles, but has leaf sheaths and parallel venation.
Stems The stem is round and herbaceous. 
Flowers Monoecious; the hollow, bead-like structure is known as an involucre. It houses 3 female flowers : one fertile flower and two sterile flowers. The fertile female flower produces 2 purple, feathery stigmas that emerge out of the hole at the apex. The male inflorescence occurs on a thin stalk that also emerges from the hole at the apex of the involucre. The male inflorescence resembles a head of wheat. It has green, herbaceous bracts that partially cover the male flowers. 
Fruit When the stigmas of the female flower catch pollen carried by the wind, fertilization occurs and a grain is formed as the fruit. The grain remains inside the involucre. The involucre is intially green, gradually becomes black and then becomes gray to white. 
Habitat Occurs in swamps, forest edges, lowlands, ditches and on stream banks. It is typically found in hot climates with moist soil. 
Cultivation This species grows best in warm, tropical climates. Plant it in soil with good drainage. Involucres containing grain should be planted at a depth of 2.5 cm with 60 cm of spacing on all sides between plants. Immature plants should be well-watered. Fertilize by regularly adding manure to the soil. As the grain sets, reduce watering to maximize yield. 
Etymology The genus "Coix" is the Latin version of a Greek name for the Egyptian palm Hyphaene thebaica. The species epithet "lacryma-jobi" means Job's tears which is a common name of this plant. The reference is to the teardrop shape of the dried fruits. Job was a man in the Bible who lived a righteous life, but suffered much hardship.
Ethnobotanical Uses Edible Plant Parts : Edible Seeds
Food (Herb and Spice): The soft-shelled grains are sometimes husked and prepared like rice or ground to make a sweet, nutritious flour. This flour can be used to make bread or mixed with water to make a drink. In Japan, the grains are used to make tea. The grains is also made into beer in the Philippines. The Chinese use the grains to make soups. 
Medicinal: The roots of this plant are thought to cure menstrual problems. The grains have antiseptic properties and can also be used to reduce fever or control muscle spasms. 
Others: The involucres (hard-shelled fruits) are typically used as ornamental beads for jewelry, rosaries or decoration for clothing. In Central America, they are used to make seed dolls. In Africa, a musical instrument known as the shaker gourd consists of a net of involucres loosely wrapped around a hollow gourd. When the net is slapped against the gourd, a rhythmic sound is produced. The plant is also used as fodder for livestock.

Landscaping Features

Landscaping In the 14th century, this species was often planted in monastery and herb gardens for its ornamental fruits. 
Desirable Plant Features Ornamental Fruits

Plant Care and Propagation

Light Preference Full Sun
Water Preference Lots of Water
Rootzone Tolerance Waterlogged Soils, Fertile Loamy Soils
Propagation Method Seed
Propagation Method Remarks Propagate by planting the involucres which contain seed inside. 

Foliar

Mature Foliage Colour(s) Green
Leaf Area Index (LAI) for Green Plot Ratio 3.5 (Shrub & Groundcover - Monocot)

Floral (Angiosperm)

Flower & Plant Sexuality Unisexual Flowers , Monoecious
Inflorescence Type Raceme

Fruit, Seed and Spore

Mature Fruit Colour(s) White
Fruit Type Indehiscent Dry Fruit , Caryopsis / Grain

Image Repository

Images

Others

Master ID 538
Species ID 1834
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: 10 September 2023.
Share