Propagating River Buttercup (Ranunculus inundatus)

How to propagate Ranunculus inundatus by dividing its creeping rhizome and runners: lift and split runner-borne plantlets, replant them, and use strong light for a compact carpet.

Overview

River buttercup (Ranunculus inundatus) is a buttercup species from eastern Australia that has become popular in freshwater aquascaping and nano aquariums. It is a low foreground plant with star-shaped, deeply divided umbrella-like leaves on slender stalks, growing from a creeping base that spreads sideways across the substrate.

According to Tropica it forms many vertical runners bearing new plants, and over time a thick bottom coverage develops. Propagation is therefore vegetative: divide the creeping rhizome and the runner-borne plantlets, not the leaves.

Propagation Method

Let the plant spread on its own runners, then divide. Lift a clump, separate the runners with their attached plantlets, and replant each piece. Each runner plantlet already has its own roots, so the new patch fills in quickly and forms fresh coverage.

Step-by-Step

Wait until the parent has sent out several runners with rooted plantlets.
Gently lift the clump or expose the creeping rhizome in the substrate.
Separate the runners, keeping each plantlet's roots intact.
Cut the rhizome between plantlets if needed so each piece carries roots and leaves.
Replant the divisions in nutrient-rich substrate, spaced a few centimetres apart.
Prune any long leaves to keep the patch compact while it establishes.

Conditions for Healthy Growth

Tropica rates Ranunculus inundatus as a medium-light plant (about 0.5 W/L) with a medium CO2 demand (6-14 mg/L) and medium growth rate, reaching roughly 5 cm in around two months. Good lighting produces compact growth with distinctly cut umbrella leaves; the knowledge base lists 18-26 C, pH 6-7.5 and a wide GH range.

Maintenance

Prune long leaves to maintain the desired height and encourage dense coverage. Thin the carpet periodically by removing and replanting runner plantlets so the patch stays even and does not shade itself out.

Common Challenges

Leggy, stretched growth: too little light, raise the lighting to keep umbrellas compact.
Slow spread: give it time to push runners and provide medium CO2 and a rich substrate.
Patchy carpet: divide and replant runner plantlets to fill the gaps evenly.