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Limnophila aromatica


Limnophila aromatica (Lam.) Merr.

Family Name: Scrophulariaceae
Synonyms: Limnophila aromaticoides
Common Name: Rice Paddy Herb, 紫苏草, 水薄荷


Family Name
Genus Epithet
Species Epithet
Name Authority
Common Names

Classifications and Characteristics

Plant Division Angiosperms (Flowering Seed Plants) (Dicotyledon)
Plant Growth Form Aquatic & Hydrophyte
Lifespan (in Singapore) Perennial
Mode of Nutrition Autotrophic


Native Distribution Southeast Asia
Native Habitat Aquatic (Freshwater Pond / Lake / River)
Preferred Climate Zone Tropical

Description and Ethnobotany

Growth Form A herbaceous, variable shrub with both an emergent and submerged form. 
Foliage The simple leaves are arranged on the stem in opposite pairs and are lanceolate-elliptic to ovate-lanceolate in shape. The leaves have a dentate margin. The submerged leaf form is less rigid and bigger in size as compared to the emergent leaf form. The leaves are green with a purple underside, under high light conditions, the submerged leaves turn red. 
Stems The stems are 30 to 70cm in length and root at the nodes. The stems of the emergent form is purple in colour. 
Flowers The flowers are only produced when the plant is above the water surface and are produced in the leaf axils. The flowers are purple with a white villous interior. 
Habitat It is found in swampy soil such as rice paddy fields, marshes and reservoirs. 
Cultivation It is best grown under full sun in consistently moist, fertile soil. It is best grown in water temperatures of 20 to 25° and in pH levels of 6.4 to 7.0. In aquascapes, the plant needs to be trimmed regularly by topping the stems to prevent it from reaching the water surface. The tops of the stems can be propagated.  
Ethnobotanical Uses Food (Herb or Spice): The herb can be eaten raw or cook. It is an important culinary herb in Vietnamese cuisines. In extensively used in fish soup, meat or fish dishes for it's special flavor.
Medicinal: The leaves of this plant immersed are used to relieve fever and mucous decoction. The refreshing aroma of leaves are also used to destress body and mind.

Landscaping Features

Desirable Plant Features Ornamental Flowers, Ornamental Foliage
Landscape Uses Parks & Gardens, Pond / Lake / River, Aquarium / Aquascape
Thematic Landscaping Water Garden, Economic Garden

Plant Care and Propagation

Light Preference Full Sun, Semi-Shade
Water Preference Lots of Water
Rootzone Tolerance Moist Soils, Waterlogged Soils (Does not Drain Site), Fertile Loamy Soils
Propagation Method Seed, Stem Cutting (Herbaceous)


Foliage Retention Evergreen
Mature Foliage Colour(s) Green
Foliar Type Simple / Unifoliate
Foliar Arrangement Along Stem Opposite, Whorled
Foliar Attachment to Stem Sessile
Foliar Shape(s) Non-Palm Foliage (Lanceolate, Elliptical)
Foliar Venation Pinnate / Net
Foliar Margin Serrate / Toothed, Crenate

Floral (Angiosperm)

Flower Colour(s) Purple
Flower Grouping Solitary
Flower Location Axillary, Terminal
Individual Flower Shape Funnelform / Funnel-shaped

Fruit, Seed and Spore

Fruit Type Dehiscent Dry Fruit , Capsule

Image Repository



Master ID 31262
Species ID 5657
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: 20 August 2021.