Ludwigia repens
The easiest red stem plant. Green-pink under medium light, deep red under high light + iron. More forgiving than Rotala, tolerates harder water and skipping CO₂. Top-and-replant for density.
Ludwigia Repens (Ludwigia repens) is a stem aquatic plant for the midground to background of a planted tank. It reaches 25–50 cm under good conditions and grows at a fast rate. Light: medium to high. CO₂: optional. Target 18–28 °C, pH 5.5–8.0, and 3–18 dGH. Substrate: Any, water column feeder, root tabs accelerate red colour. Propagate via cuttings.
Care at a glance
The easiest red stem plant. Green-pink under medium light, deep red under high light + iron. More forgiving than Rotala, tolerates harder water and skipping CO₂. Top-and-replant for density.
By Mike ElmiraUpdated 2 min read
Part of our complete guide to the planted aquarium.
The parameters that decide whether ludwigia repens fits in your tank.
Onagraceae
Stem
Midground to Background
Any, water column feeder, root tabs accelerate red colour
Cuttings
Swampy ditches and pond edges of the Americas
Central America to southern USA
Tank-mate safety and the species this one is documented to thrive (or fail) alongside.
Hard-won lessons from the tank.
The single most forgiving red plant. Skip CO₂ if you must — you'll lose some red intensity but the plant survives. For deep red: dose iron 2–3× per week, aim for 60+ PAR at the substrate, keep nitrates 5–15 ppm. The undersides of the leaves always show red regardless of conditions — look there to check if your tank can grow red plants AT ALL.
What can go wrong and how to spot it.
Failure modes, in order of how dramatic the fix is.
Pale top growth: iron or trace deficiency. Drop leaves: nitrogen or potassium deficiency. Stretchy/leggy: insufficient light. Stays green under high light: needs more iron.
Rapid growth outcompetes algae. Old leaves at the base can attract spot algae — trim and replant from the top.
The practical routine, read top to bottom.
Moderate water column feeder. Iron-rich fertilizer for red colour. Root tabs help but not essential. CO₂ optional — speeds growth but not required.
Top weekly — cut the top 5–10 cm just above a node and replant. Side shoots branch from the trimmed node. Replant cuttings densely for a bushy red mass.
Where it comes from, how it behaves, and the variants you'll see at retail.
Where it lived before it came home.
Slow streams, ditches, and pond edges across Central America and southeastern USA. Hardy across temperate and tropical climates, often growing partially emersed on muddy banks.
Grows easily emersed with stiff oval leaves, green tops, purple undersides. Almost all wholesale arrives emersed and transitions to submerged form within 2–3 weeks.
Small yellow flowers emersed; rarely flowers underwater.
The named cultivars and the lookalikes worth flagging.
L. repens (standard, copper-green), 'Rubin' (deeper red), L. repens × arcuata 'Mini Super Red' (compact, intensely red, premium), 'Diamond' (white-spotted leaves), 'Hybrid' (vigorous standard cultivar). All grow similarly; redness varies with light and iron.
L. repens often confused with L. palustris (also called 'red repens') and L. natans. L. arcuata is a different needle-leaved species. Many 'Ludwigia super red' labels are actually L. glandulosa hybrids.
Direct answers to the questions search engines and AI assistants surface most often about this species.
CO₂ requirement: optional. Light requirement: medium to high. Under low-tech conditions the plant grows at a fast rate.
Ludwigia Repens (Ludwigia repens) needs medium to high light. Run a photoperiod of 6–8 hours; longer photoperiods invite algae unless CO₂ and dosing are dialled in.
Position: midground to background. Substrate: Any, water column feeder, root tabs accelerate red colour It typically reaches 25–50 cm.
Propagation method: Cuttings. Ludwigia Repens is a stem plant.
Target 18–28 °C, pH 5.5–8.0, and 3–18 dGH. Flow tolerance: low to medium.
Difficulty: 2/5. Forgiving, beginner-friendly once the tank is cycled.
A planted tank is a system. Pair this plant with one entry from each other pillar to plan the whole scape.
