Ludwigia repens

Overview

Ludwigia repens is one of the easiest red stem plants and a great first step into coloured aquascaping. Its rounded leaves are green on top with red-to-bronze undersides, deepening to full red under strong light. As a fast-growing stem plant it is trimmed and replanted to shape, and its speed makes it an effective nutrient sponge that helps keep algae in check. Undemanding enough for low-tech tanks, showy enough for high-tech ones.

Planting & placement

Plant Ludwigia stems individually into the substrate, a centimetre or two apart, so a group grows into a full bush. It works in the midground and background, where the red contrasts beautifully with green plants like Rotala rotundifolia or a bright carpet. Strip the lowest leaves before planting the stem. See how to plant aquarium plants for the technique.

Light, CO2 & ferts

Ludwigia grows in medium light with no CO2 required, staying greenish-bronze. For full red colour and compact growth, add high light and optional CO2. Feed a complete liquid fertilizer with iron to support the reds; as a fast grower it appreciates steady feeding. See best aquarium plant fertilizer for options.

Propagation & problems

Propagate by trimming and replanting: cut the top of a healthy stem and plant it — it roots readily — while the cut parent branches and thickens. This is also how you keep the group dense and the reds at the well-lit top. Common problems are leggy, pale growth (raise light and CO2) and lower-stem leaf drop as the canopy shades the base (thin the group and replant tops). Otherwise it is a robust, rewarding plant. Its fast growth also makes it a useful nutrient sponge that helps starve out algae in a well-lit tank. For the fullest effect, plant a dense group and keep trimming and replanting the tops — each trim gives you more plants and encourages the parent stems to branch into a thick, red-tipped bush.