Ludwigia glandulosa

Overview

Ludwigia glandulosa (sometimes sold as ‘Perennis’) is a striking stem plant grown for its narrow, deep purple to burgundy leaves — one of the darkest reds you can achieve in a planted tank. That colour comes at a price: it is a demanding plant that needs high light, CO2 and generous iron to show its best. In a low-tech tank it survives as an unremarkable olive-green stem; in a high-tech one it becomes a dramatic midground or background accent.

Planting & placement

Plant the stems individually into a nutrient substrate, spacing them slightly so light reaches every stem, as our how to plant aquarium plants guide shows. A small group of stems reads as one bold splash of colour in the midground to background. It contrasts beautifully against green plants like rotala and pairs with other reds such as Ludwigia super red in a colourful aquascape.

Light, CO2 & ferts

This is a high-tech red. Strong light is what triggers the purple pigment — under weak light it stays green. Inject CO2 for healthy, algae-free growth, and dose iron plus a full micronutrient fertilizer, which reds rely on for colour and to avoid stunting. See our best light for a planted tank and best aquarium plant fertilizer guides.

Propagation & problems

Propagate by top cuttings: trim the top few centimetres of a healthy stem and replant it; the cut stem branches from below, so trimming both multiplies the plant and thickens the group. Common problems are green (not red) colour from weak light or low iron, and bare lower stems when light can’t reach the base of a dense clump — thin the group and keep nutrients and CO2 stable. It grows at a moderate pace rather than explosively, so it is less maintenance-hungry than many stem plants once dialled in. Stable CO2 and consistent dosing matter more than sheer light intensity for avoiding the stunted, twisted new growth reds are prone to. Meet its needs and Ludwigia glandulosa is one of the most rewarding dark reds in the hobby, holding a colour few other plants can touch.