Bacopa sp. "Japan"

Bacopa sp. 'Japan' is a trade name for Bacopa serpyllifolia (Benth.) Pennell.¹ Despite its name, this annual or subshrubby species comes from South America, where it occurs from southern Venezuela and Guyana to north-eastern Argentina.² It is one of the eight species of the genus cultivated in the aquarium and pond trade.³

With mostly creeping to obliquely ascending shoots, this stem plant, 5–20 cm tall, forms carpets or low, dense bushes; its elongated leaves are a vivid yellow-green.¹ It only thrives with strong light and plenty of CO₂ and iron, and newly planted specimens sometimes need time to establish.¹ It is planted as a group or ground cover in the foreground and midground.¹

1. Bacopa serpyllifolia – Flowgrow aquatic plant database (accessed 5 October 2026)
2. Bacopa serpyllifolia – Plants of the World Online, Royal Botanic Gardens Kew (WCVP data as of 4 June 2026, accessed 5 October 2026)
3. Bacopa – Aquarium and Pond Plants of the World, USDA APHIS ITP, idtools.org (accessed 5 October 2026)