Hydrocotyle tripartita
Hydrocotyle tripartita
Also known aspennywort · hydrocotyle Japan · hydrocotyle sp. Japan
Water parameters
Light and nutrients
Substrate type: rooted. Propagation: runners.
Substrate compatibility
| Substrate | pH effect | Nutrient load |
|---|---|---|
| Aquasoil (ADA Amazonia) | lowers pH | very high |
| Dirted tank (mineralized topsoil) (DIY soil substrate) | slightly acidic | very high |
| Mineralized clay substrate (Seachem Fluorite) | neutral / inert | moderate |
| Inert sand (Pool filter sand) | neutral / inert | none |
| Inert gravel (Aquarium gravel) | neutral / inert | none |
With fish
Origin and habitat
Native to Southeast Asia and Australia, found in wet meadows, stream margins, and shallow water. The species (Hydrocotyle tripartita, commonly called hydrocotyle or 'Japan' in the hobby) has small, clover-like trilobed leaves (each leaf divided into three rounded lobes) on thin, creeping stems. The overall effect is a delicate, carpeting ground cover with a distinct clover-leaf texture. The 'Japan' trade name is misleading; the plant is from Southeast Asia, not Japan. Introduced to the aquascaping hobby in the 2000s, it quickly became popular for its ability to carpet, climb, and grow over hardscape, creating a naturalistic mossy-carpet look that's different from the grass-like texture of Eleocharis or Sagittaria. Several related Hydrocotyle species are sold under similar names; H. tripartita 'Japan' is the most common. True H. verticillata and H. leucocephala are different species with larger, rounder leaves and a more upright growth habit.
Care notes
A versatile plant that carpets the foreground, climbs up hardscape, and cascades over rocks and driftwood. Moderate to high light produces the tightest, most compact growth. Under low light, the stems elongate and the plant becomes leggy. CO2 injection is strongly recommended for carpet-like growth; without CO2, it grows slowly and tends to climb rather than carpet. Rich substrate supports root-zone feeding but the plant also absorbs nutrients from the water column through its leaves. Plant small portions and press them into the substrate; the creeping stems root at each node. Growth under optimal conditions (high light, CO2, nutrients) is fast: the carpet fills in within 4-6 weeks. Trim frequently with scissors to maintain a low, dense carpet; if left untrimmed, the stems pile on top of each other and the lower layers die from light deprivation. The climbing habit means the plant will grow up driftwood and rocks if it reaches them, creating a unique draped effect. This can be a feature or a nuisance depending on the aquascape design. Temperature: 20–28°C. pH 6.0-7.5. Propagation by stem cuttings or division; any fragment with a node can root and grow. A popular mid-level difficulty plant for aquascapers who want a carpet with a distinct texture.