Propagating Salvinia cucullata (Hooded Floating Fern)

How to multiply Salvinia cucullata, a fast free-floating fern with cup-shaped hairy leaves, by splitting its floating stems into daughter pieces and thinning the mat.

Overview

Salvinia is a genus of free-floating aquatic ferns in the family Salviniaceae. Its leaves grow in three-part whorls of two green floating leaves plus one finely dissected, root-like submerged leaf, and the plant has no true roots. The floating leaves carry hairlike trichomes that make the surface water-repellent. Salvinia cucullata is a hooded, cup-shaped floater whose free-standing hairs measure roughly 0.3–3 mm.

Under good light and nutrition it grows quickly, forming a dense surface mat that shades the tank below — useful for shy fish and for starving out algae, but something that must be kept in check.

Propagation Method

Like the rest of the genus, Salvinia cucullata reproduces vegetatively by fragmentation and division. Because the floating stems branch and bud, any piece that breaks off or is deliberately separated can grow on as an independent daughter plant. This is the only practical home-aquarium method — there is no need for cuttings, spores or sporocarps.

Step-by-Step

Choose a healthy, dark-green section of the floating mat with intact cup-shaped leaves.
Gently pull or pinch the connected floating stems apart into smaller daughter pieces; each fragment with a few leaves will continue to grow.
Skim off the separated pieces with a cup or net so the water-repellent leaves are not pushed under.
Float the daughter pieces, hairy side up, on the surface of the destination tank.
Keep surface flow low for the first days so the fragments are not driven against the glass or under the water line.

Conditions for Healthy Growth

Lighting: low to medium light is enough; brighter light speeds growth.
CO2: not required.
Temperature: roughly 20–30 °C suits this tropical floater.
Nutrients: it draws nutrients straight from the water column; pale, light-coloured leaves signal a shortage of micronutrients.
Flow: calm water with little surface current gives the best growth.

Maintenance

Thin the mat regularly so it does not seal the entire surface; removing portions keeps light reaching plants on the bottom and lets gas exchange continue. The pieces you remove are your propagation stock — share, move them to another tank, or compost them.

Common Challenges

Pale or light leaves: usually a micronutrient deficiency — dose a complete fertiliser.
Leaves wetting and sinking: strong surface flow or condensation breaks the water-repellent hair layer; reduce flow and avoid splashing.
Runaway coverage: fast growth can shade and starve bottom plants, so trim before the mat closes over completely.