Fern-Leaf Hygrophila
Hygrophila pinnatifida
Acanthaceae
About
Hygrophila pinnatifida is the odd one out in a genus otherwise known for plain upright stems. Its submersed leaves are cut deep into lobes, so a settled clump reads as a low fern rather than a stem plant, and the colouring is unusual too: olive to leathery brown above, with a pale yellow flare where each side vein leaves the midrib, and wine red on the underside. It also grows sideways. Alongside upright shoots it pushes out creeping, runner-like laterals whose roots grip wood and stone the way an epiphyte does, so a single plant can be set into the substrate, tied onto a branch, or both at once. That is a different animal from the three hygros already in this catalogue: Temple Plant (H. corymbosa) is a big fast background stem, Dwarf Hygrophila (H. polysperma) a near-indestructible low-light filler, and Water Wisteria (H. difformis) a soft feathery grower - all three root only in substrate, and all three forgive far more. Pinnatifida comes from streams at the foot of the Western Ghats in India and has only been cultivated for aquariums since 2008.
Care
This is not a beginner plant. It survives at medium light but stretches and thins out; brighter light plus CO2 is what keeps it compact and coloured, and without CO2 expect slow, sparse growth that algae colonise before the plant fills in. Dose macros and micros steadily and watch potassium in particular - pinprick holes in the older leaves are this species' signature deficiency. Pinch the upright tips regularly to drive it into horizontal side shoots, which are also the best cuttings. Tie or gel-glue it to hardscape if you want the creeping habit; substrate quality matters little, since the root system stays small and shallow. The stems are tough for a hygro, but goldfish and large cichlids will still wreck it.
Frequently asked questions
- What water parameters does a Fern-Leaf Hygrophila need?
- Fern-Leaf Hygrophila does best at 18–28 °C (64.4–82.4 °F), pH 5–8 and a general hardness of 2–20 °dGH.
- Where should Fern-Leaf Hygrophila be placed in the aquarium?
- Fern-Leaf Hygrophila works best in the midground and reaches around 40 cm.
- Is the Fern-Leaf Hygrophila suitable for beginners?
- Fern-Leaf Hygrophila sits in the middle of the difficulty scale — manageable for a careful beginner who has done the reading, but it has specific needs worth researching first.