Bacopa monnieri
(water hyssop)

Preferred Scientific Name

• Bacopa monnieri (L.) Wettst.

Preferred Common Name

• water hyssop

Other Scientific Names

• Anisocalyx limnanthiflorus (L.) Hance
• Bacopa micromonnieria (Griseb.) B.L.Rob
• Bramia indica Lam.
• Bramia micromonnieria (Griseb.) Pennell
• Bramia monnieri (L.) Drake
• Bramia monnieri (L.) Pennell
• Calytriplex obovata Ruiz & Pav.
• Capraria monnieria Roxb.
• Gratiola monnieri (L.) L.
• Gratiola portulacacea Weinm.
• Gratiola tetrandra Stokes
• Habershamia cuneifolia (Michx.) Raf.
• Herpestis cuneifolia Michx
• Herpestis micromonnieria Griseb.
• Herpestis monnieri (L.) Kunth
• Herpestis monnieri (L.) Rothm.
• Herpestis procumbens Spreng.
• Limosella calycina Forssk.
• Lysimachia monnieri L.
• Monniera cuneifolia Michx.
• Septas repens Lour.

International Common Names

• English: bacopa; coastal water-hyssop; herb-of-grace; white hyssop
• French: bacopa de monnier; bacopa des herbalistes; bacopa médicinale; bramia de saint-paul; petite bacopa
• Chinese: jia ma chi xian

Local Common Names

• Cambodia: snau
• El Salvador: verdolaga
• India: adha-birni; afed chamni; brahmi; farfakh; gundala; Indian-pennywort; indravalli
• Lesser Antilles: veronique
• Malaysia: beremi
• Mexico: baraima
• Philippines: ulasimang-aso
• Puerto Rico: yerba de culebra
• Thailand: phak mi; phrommi
• Vietnam: rau sam

• Domain: Eukaryota
•     Kingdom: Plantae
•         Phylum: Spermatophyta
•             Subphylum: Angiospermae
•                 Class: Dicotyledonae
•                     Order: Scrophulariales
•                         Family: Scrophulariaceae
•                             Genus: Bacopa
•                                 Species: Bacopa monnieri

The genus Bacopa has been assigned to the family Plantaginacae, following the disintegration of the family Scrophulariaceae (Olmstead et al., 2001; Olmstead, 2002), with Plantaginacae taking precedence over the younger proposed family name Veronicaceae.

Plantaginaceae is a diverse family comprising approximately 90 genera and 1900 species distributed mostly across temperate regions but also occurring in tropical and subtropical areas. Species within Plantaginaceae include herbs, shrubs and aquatic plants that can be distinguished by two features: the frequent absence of regular vertical partitions in the heads of the glandular hairs and septicidal capsule dehiscence (Stevens, 2017).

The genus Bacopa comprises approximately 55 to 70 species of aquatic herbs (most of which grow as amphibious plants) distributed across tropical and subtropical regions of the world. Bacopa is sometimes confused with other small prostrate herbs like Lindernia, Callitriche, Stemodia and Mecardonia that may be found in similar habitats (Flora Mesoamericana, 2017; Flora of China Editorial Committee, 2017; The Plant List, 2013; Flora of Panama, 2017).

Herbs prostrate to decumbent, succulent, glabrous. Stems creeping, to 50 cm, loosely ascending, rooting at nodes, much-branched. Leaves sessile, 0.5-2 cm by 0.15-0.8 cm, oblong-oblanceolate, the bases cuneate, the margins entire or denticulate, the apices rounded, with 1-3 parallel veins from the base of the blade, glabrous. Inflorescences of solitary axillary flowers; pedicels 0.5 cm to 1(-3.5) cm; bracteoles 2, 1.3-4.5 mm, lanceolate-linear, below calyx. Calyx 4.2-7 mm; outer 3 sepals succulent, ovate-lanceolate, apices rounded, inner 2 lanceolate to linear, keeled, ciliate. Corolla 6-9 mm, campanulate, 5-lobed, nearly regular, but the lower central lobe somewhat longer and more separated from the other lobes, white, pink or lavender blue, often with purple lines, the throat dark purple, the tube yellow within. Stigma capitate, united. Capsule 4.5-5 mm, ovoid, enveloped in persistent calyx; seeds numerous 0.5 mm long, longitudinally reticulate, the reticulum reddish brown (Flora Mesoamericana, 2017; Flora of Panama, 2017). 

Intentional introduction

B. monnieri has been intentionally introduced by humans to be grown as a medicinal herb and also as an ornamental plant in ponds and aquaria (USDA-ARS, 2017). It is listed as introduced and invasive in Japan, Singapore, Spain, Portugal and the Cayman Islands (​Díaz and Beiras, 2007​; APASD, 2007; DAISIE, 2017; ISSG, 2017; GRIIS, 2017).

Soil drainage

• seasonally waterlogged

Soil reaction

• alkaline
• neutral

Soil texture

• light

Special soil tolerances

• saline

B. monnieri spreads both by seeds and vegetatively by stem fragments. Seeds and stem fragments are commonly spread by waterways and floods, with new plants developing rapidly from any piece of stem or root material containing a node (PROSEA, 2017).

B. monnieri is a weed of terrestrial and aquatic habitats, forming dense mats in wetlands, wet pastures, rice fields, irrigated areas, riversides and coastal areas. In aquatic habitats, it has deleterious effects on native plants and animals, water quality, water flow and sedimentation. In terrestrial situations, it degrades riverbanks, margins of ponds, lakes and coastal areas. It has been listed as invasive in Japan, Singapore, Portugal, Spain and the Cayman Islands (​Díaz and Beiras, 2007​; APASD, 2007; Varnham, 2009; DAISIE, 2017; ISSG, 2017; GRIIS, 2017).

• Proved invasive outside its native range
• Has a broad native range
• Abundant in its native range
• Highly adaptable to different environments
• Is a habitat generalist
• Tolerates, or benefits from, cultivation, browsing pressure, mutilation, fire etc
• Highly mobile locally
• Benefits from human association (i.e. it is a human commensal)
• Long lived
• Fast growing
• Gregarious
• Reproduces asexually

• Damaged ecosystem services
• Modification of hydrology
• Monoculture formation
• Negatively impacts agriculture
• Reduced amenity values
• Reduced native biodiversity
• Threat to/ loss of native species

• Rapid growth
• Rooting

• Highly likely to be transported internationally deliberately
• Difficult to identify/detect in the field

Productive Uses and Management

B. monnieri is a medicinal plant used for centuries in traditional Indian medicine and in Ayurveda medicine. It is widely promoted to enhance memory, learning and concentration and also to treat anxiety, depression, and cardiovascular, gastrointestinal, hepatic, neurological and respiratory problems. Plant extract and isolated bacosides (the major active components) have been extensively investigated in laboratory and clinical tests for their neuropharmacological effects and nootropic action. Studies have suggested that the active ingredients within B. monnieri may improve memory, attention, cognition and mood (Pase et al., 2012). In Peninsular Malaysia and Vietnam, the plant is sometimes eaten as a vegetable despite its bitterness. It is also a very popular aquatic plant among aquarium fish keepers (Russo and Borrelli, 2005; Charoenphon et al., 2016; PROSEA, 2017; USDA-ARS, 2017).

 Economic value

In India, B. monnieri is cultivated as a medicinal plant. The dried herb is found in several Indian herbal nutritional supplements called "Smart Drugs", specifically for cognitive enhancement, reducing fatigue and forgetfulness. Across South East Asia, herbalists trade the dried plant in pharmacies (PROSEA, 2017).