Dwarf rotala (Bonsai)

Overview

Dwarf rotala ‘Bonsai’ (Rotala rotundifolia ‘Bonsai’) is a compact cultivar of the familiar Rotala rotundifolia, selected for its small, rounded leaves and very short internodes. Where standard rotala grows tall and is used in the background, ‘Bonsai’ stays low and dense, making it one of the few stem plants versatile enough to work as a foreground or low-midground bush. Under strong light with CO2 it forms tight, cushion-like clusters; grown dimly it stretches and loses the miniature charm that gives it its name. It is a lovely detail plant for a well-lit scape.

Planting & placement

Dwarf rotala is a stem plant, but a short one. Plant the small stems individually into the substrate close together with tweezers, in a dense group — spacing them tightly is what builds the low, carpet-like cushion this variety is grown for. It suits the foreground or midground, where its fine texture and low profile shine. See how to plant aquarium plants for the tweezer technique and aquascaping for beginners for using low bushes in a layout.

Light, CO2 & ferts

Compactness depends on light. Give it medium-to-high light — our best light for a planted tank guide can help — to keep the internodes short and the plant low; under weak light it stretches tall and loses its form. Injected CO2 is recommended for the tightest bonsai growth. Dose a complete fertilizer from our best plant fertilizer picks to keep the small leaves healthy and green.

Propagation & problems

Propagate by trim and replant. Snip the tops and push the cuttings back into the substrate close together — they root fast and thicken the carpet, while the trimmed stems branch densely below the cut. Frequent trimming is the main tool for keeping it low and full. The common problems are stretching and loss of compactness from insufficient light, and thin patches from underfeeding — high light, CO2 and steady ferts solve both. Give it those, and dwarf rotala ‘Bonsai’ becomes a beautifully detailed low bush few other stems can imitate.