Ludwigia atropurpurea Care Guide
Ludwigia atropurpurea is a South American stem plant of the family Onagraceae, grown for dark purple-red foliage under bright light with CO2.
Compiled by Aquairi from published sources · Published · Updated
Overview
Ludwigia atropurpurea is an aquatic stem plant of the genus Ludwigia within the family Onagraceae. Ludwigia comprises roughly 82 species with a cosmopolitan but mainly tropical distribution, the majority centred in South America. The plant is grown as a colour accent for its dark purple-red foliage, which develops most strongly under good lighting and nutrient supply.
Taxonomy
- Family: Onagraceae
- Genus: Ludwigia
- Scientific name: Ludwigia atropurpurea
- Common name: Dark-purple Ludwigia
Habitat
Species of Ludwigia characteristically grow in wet habitats, and some are nearly or fully aquatic, with adaptations such as aerenchyma for life in water. Ludwigia atropurpurea is of South American origin, where the genus reaches its greatest diversity.
Aquarium requirements
- Temperature: 22-28 °C (72-82 °F)
- pH: 5.5-7.0
- GH: 1-8 °dGH
- Lighting: high
- CO2: required
- Maximum height: up to about 35 cm
- Placement: mid-to-background
Growth and care
This is a moderately fast stem plant with high nutrient demand. Soft, slightly acidic water, a nutrient-rich substrate, CO2 injection and a steady micronutrient supply, including iron, support the dark purple-red colouration. Insufficient light or nutrients diminish the colour intensity.
Propagation
Ludwigia atropurpurea is propagated by cuttings. Trimming the shoot tip promotes lateral branching, and cut tops can be replanted to establish new plants. Regular trimming maintains a compact, well-shaped group.
Propagating Ludwigia atropurpurea (Dark-purple Ludwigia)
Overview
Ludwigia atropurpurea is a stem plant of the family Onagraceae prized for very dark purple-red foliage under strong light and good nutrition. It grows upright as a background or mid-ground accent and, like its red ludwigia relatives, only shows its deepest color when light, CO2 and fertilization are all in balance.
Propagation Method
It branches willingly and is propagated by cuttings and topping. Cutting the top of a stem yields a replantable cutting while the base responds by pushing new side shoots, so topping both multiplies stems and builds a denser purple group.
Step-by-Step
- Cut the stem at a node below the height you want, staggering cuts across the group for a slope.
- Take a 5–10 cm top cutting and strip the lower leaves to expose a clean node.
- Plant the bare node into nutrient-rich substrate and let it anchor.
- Keep the topped base; side shoots emerge at the cut and can be split off later.
- Trim away any outlying shoots that break the slope to keep tidy clusters.
Conditions for Healthy Growth
Purple intensity rises with light: about 70–80 umols PAR gives good color and high light (80 umols+) also drives more side shoots. At least 10 ppm CO2 improves color and branching, with roughly 30 ppm suiting most demanding reds. Iron and balanced nutrients in the column or substrate sustain the dark pigment.
Trimming & Maintenance
Trim about every 7–10 days. Repeated pruning at the node thickens the bush as the base branches, and every removed top is a fresh plant. Stagger the cutting height to keep a layered purple background.
Common Challenges
- Color loss: low light, CO2 or iron turns foliage green instead of deep purple.
- Leggy growth: too little light stretches stems and thins the lower leaves.
- Import melt: emersed-grown stems may shed leaves before adapting to submersed purple growth.