Bacopa monnieri aka Monnier's Hedge Hyssop

Bacopa monnieri is known as water hyssop or brahmi. It belongs to the Plantaginaceae family. Its native range spans tropical and subtropical parts of the world. These include the Americas, India, and Southeast Asia. In the southeastern United States, it grows along the coastal plain. Its range there runs from Virginia to Florida and Texas. It lives on wet shores, marshes, and stream banks. It also grows beside water channels and in irrigated fields.

This creeping herb forms mats and spreads fast in wet ground. Garden sources describe it as a perennial with evergreen leaves. One source gives a height of about 0.16 feet [0.05 metres]. Its branched stems reach 0.16–1.31 feet [0.05–0.4 metres] long. They root at the nodes as they spread. The stems are green, smooth, and lack scent. Small, thick leaves grow in pairs along the stems. Their oval blades have smooth edges and a fleshy feel. Crushing the leaves does not release a scent.

Single flowers grow where leaves meet the stem. Each bell-shaped bloom has four or five petals. The flowers are white, sometimes tinted pink or blue. North Carolina State records bloom from April until frost. Chicago Botanic Garden lists May through October. In warm regions, flowers and fruit may appear most of the year. North Carolina State records fruit from June through November. The long bloom season adds interest to wet beds and pots.

Water hyssop grows in full sun or part shade. It needs moist to wet soil or shallow water. It handles heat and salt, but does not withstand drought. Clay, loam, and sand can support it when kept wet. It also accepts acid, neutral, and alkaline soil. Sources list USDA zones 8–11, though Chicago gives 8–9. Gardeners use it in bog gardens, pond edges, and aquariums. Its stems can trail from pots and hanging baskets. It feeds white peacock butterfly larvae and attracts adult butterflies. Deer show some resistance to eating it.

North Carolina State reports no known pest or disease problems. The plant needs little upkeep, though its spread can become weedy. People eat the leaves raw, cooked, pickled, or in soups. Flowers also serve as food during shortages. Large servings can cause nausea and gut upset. Wild plants can absorb heavy metals from polluted sites. Brahmi has a long history of use in Ayurvedic medicine. That history alone does not establish safe or effective treatment.