About the species

Ludwigia repens 'Rubin' is the hobby's classic red stem plant, with deep red leaves and a red stem. The stems reach 20–50 centimetres tall and four to six centimetres wide, and the colour intensifies the stronger the light. It has few demands and ranks among the very most reliable red plants there are.

Facts

• Latin name: Ludwigia repens 'Rubin'
• Plant type: Stem plant
• Origin: North America
• Height: 20–30 cm
• Growth rate: Medium
• Position: Background

Light requirement

Medium light requirement. Reckon on around 0.5 W per litre or a modern mid-range LED unit. Too little light gives sparse, stretched shoots and pale leaves, while the right amount keeps the plant compact and richly coloured.

CO₂ & nutrition

Manages entirely without added CO₂, which makes it as suitable for a simple aquarium as for an aquascape. Liquid carbon or injected CO₂ speeds up growth but is never a requirement. Dose an all-round fertiliser with iron and micronutrients every week.

Planting

Split the bunch and set the stems one by one, about two centimetres into the substrate and two to three centimetres apart. Removing the lowest leaves first stops them rotting in the substrate. A group of five to ten stems looks far better straight away than single plants.

Carefully remove the pot and rinse the rock wool off the roots before planting — leftover rock wool can otherwise hinder rooting.

Care & propagation

Top the plant when it reaches the height you want and replant the cuttings — that propagates it and gives a denser group at the same time. Trim regularly so light reaches the lower leaves, and discard the old lower sections once they start thinning out.

Position in the aquarium

Given its mature height it belongs at the back or along the sides, where it forms a dense wall of greenery and hides equipment. In a smaller aquarium it can also be used as a solitaire in one corner.

Difficulty level

🟢 Easy — grows in most aquariums without CO₂ and under ordinary lighting.

Delivery format

Delivered as a pot grown submerged, with the roots in rock wool. The pot holds several plants or stems that can be divided and planted separately.

Recommendation

Plant it in a large group at the back — the contrast against all the green is the whole point and a single stem makes no impression. Trim regularly, otherwise the lower leaves drop as the group shades itself.