Propagating Philippine Java Fern: Rhizome Division & Plantlets

Propagate the hardy Microsorum pteropus 'Philippine' Java fern by rhizome division and by the adventitious plantlets that form on its leaves, keeping the rhizome exposed.

Overview

Microsorum pteropus, the Java fern, is an aquatic fern of the family Polypodiaceae found across Southeast Asia, including the Philippines. The 'Philippine' form has strongly bullate, deeply textured leaves and is a hardy, low-light epiphyte. Java ferns attach to surfaces rather than rooting in substrate, anchoring to rocks and driftwood by their rhizome.

This fern offers two easy propagation routes: dividing the rhizome, and the adventitious daughter plantlets that develop on its leaves. Both produce genetically identical new plants.

Propagation Method: Rhizome Division & Plantlets

For division, the rhizome is cut into pieces, each keeping leaves and roots so it can re-anchor and grow. Separately, the fern reproduces asexually through tiny plantlets that form at the edges and tips of the leaves; these develop their own roots, eventually drop off, and can attach to nearby objects or float to a new location.

Step-by-Step

1. For division, cut the rhizome into pieces, leaving leaves and roots on each section.
2. Attach each piece to rock or wood by tying it with thread or using super glue gel; the fern will also attach naturally with its roots.
3. For plantlets, wait until daughter plants on the leaf edges and tips have grown small roots, then gently detach them.
4. Tie or glue detached plantlets onto décor, or let them float until they anchor on their own.
5. Keep the rhizome exposed in all cases and never cover it with substrate.

Conditions for Healthy Growth

Java fern tolerates most lighting and thrives from low to medium-high light; very intense light can burn or melt the leaves. It needs no CO2 and accepts a wide range of water conditions, from soft acidic to alkaline. It is hardy, snail-resistant and left alone by most fish, with no substrate required.

Maintenance

Maintenance is minimal: trim away any blackened or fully decayed leaves and keep the rhizome clear of debris. You can harvest mature plantlets at any time to grow new plants, or leave them to spread naturally.

Common Challenges

When stressed, Java fern may push out a flush of emergency plantlets, sometimes many per leaf, signalling that conditions or the parent leaf are declining. A buried rhizome rots, and very strong light burns leaves, so the most common problems trace back to placement and lighting.