Propagating Bolbitis heudelotii: African Water Fern Rhizome Division

A practical guide to propagating the African water fern, Bolbitis heudelotii, by rhizome division and mounting it on wood or rock in soft, flowing water.

Overview

Bolbitis heudelotii, the African water fern, is an epiphytic fern with dark-green, finely divided pinnate leaves 15-40 cm long that grow fully submerged. Threadlike rootlets extend from its horizontal rhizome to grip rocks and wood. It is a slow grower that, given time, can develop into an impressive bush, and it does best in soft, moderately acidic water with good flow.

Propagation Method: Rhizome Division

Bolbitis is propagated by division of the rhizome - divisions and cuttings taken from the branching horizontal rhizome. You cut the rhizome into sections, each keeping a few fronds and some of the threadlike rootlets, and grow each section on as a separate plant secured to hardscape.

Step-by-Step

Lift the fern and rinse the rhizome to see where it branches.
With a clean blade, divide the rhizome into sections, each with several healthy fronds and rootlets.
Attach each section to driftwood or rock with super-glue gel or sewing thread, keeping the rhizome on top of the surface.
Place the mounts in a shaded spot with steady flow across the fronds.
Wait as the rootlets grow and wrap around the hardscape, anchoring the division permanently.

Conditions for Healthy Growth

Bolbitis prefers soft, moderately acidic to neutral water (pH around 5.0-7.0) at 20-28 C and does best in flowing water, mirroring its native fast-moving streams. It tolerates a wide range of light but grows best in a rather shady position. Added CO2 can enhance growth but is not required.

Maintenance

Keep flow moving across the fronds and avoid crowding, as Bolbitis is intolerant of crowding and fish waste. Remove old or damaged fronds at the rhizome. Because growth is slow, divisions need weeks to establish; resist the urge to move them while the rootlets are still gripping.

Common Challenges

Rhizome rot if it is buried in substrate - always mount it on top.
Poor growth in stagnant water; this fern needs flow.
Sensitivity to crowding and accumulated fish waste.
Slow recovery after division, which is normal for this species.