Dwarf four-leaf clover: the low-tech carpet
Marsilea hirsuta
A hardy clover-like carpet that grows without CO2 — slow but forgiving.
Where it comes from
Marsilea hirsuta is an aquatic fern from Australia, found in seasonal wetlands. Unusually for a fern it spreads by creeping runners just under the substrate, sending up leaves as it goes.
What to expect
The plant is a shape-shifter. Emersed or in low light it produces the familiar four-lobed clover leaf; submersed under good light it often reverts to simple single-lobe leaves and stays very low. Both are healthy — the four-leaf clover look is a bonus, not a sign of health.
How to keep it
Its appeal is that it carpets without CO2, which almost no other foreground does well. The trade-off is speed: it is slow to fill in and needs patience. Good light keeps it low and dense; in dim tanks it grows taller and thinner. A root-tab-fed nutrient substrate speeds establishment.
| Parameter | Value |
|---|---|
| Lighting | Medium to high keeps it low and clovery |
| CO2 | Not required; beneficial |
| Temperature | 20–26 °C |
| pH | 6.0–7.5 |
| Hardness | Soft to hard |
| Fertiliser | Root tabs help |
| Substrate | Any; nutrient-rich is better |
| Growth rate | Slow |
| Placement | Foreground |
| Difficulty | Medium |
How to carpet it
Separate the pot into small clumps and plant them across the foreground; the runners knit the gaps together over weeks. It propagates simply by lifting and dividing an established mat.
What goes wrong
The main frustration is impatience — it genuinely is slow. New plants also often melt their emersed leaves before submersed growth appears; see our guide to plant melt. Give it light, feed the roots, and wait, and it becomes a tough, permanent lawn.
More plants in this series
- Monte Carlo (Micranthemum tweediei) — the easier bright carpet
- Dwarf sagittaria (Sagittaria subulata) — the grassy low-tech carpet
- Dwarf hairgrass — the fine grassy carpet