Ludwigia repens
Ludwigia repens
Also known asCreeping primrose-willow · Red ludwigia
Water parameters
Light and nutrients
Substrate type: any. Propagation: cuttings.
Substrate compatibility
| Substrate | pH effect | Nutrient load |
|---|---|---|
| Inert sand (Pool filter sand) | neutral / inert | none |
| Inert gravel (Aquarium gravel) | neutral / inert | none |
| Aquasoil (ADA Amazonia) | lowers pH | very high |
| Mineralized clay substrate (Seachem Fluorite) | neutral / inert | moderate |
| Dirted tank (mineralized topsoil) (DIY soil substrate) | slightly acidic | very high |
With fish
Origin and habitat
A red-and-green stem plant of the evening-primrose family, Onagraceae, Ludwigia repens, the creeping primrose-willow, native across the Americas from the United States south through Central America to El Salvador and into the Caribbean, in marshes, ditches, pond margins and shallow water. It is one of the most popular and easiest red-green stems in the hobby. The upright stems carry opposite pairs of rounded to oval leaves with a signature two-tone look: the new upper leaves flush red under good light while the older lower leaves stay dark green, giving a gradient along each stem. It grows emersed or submersed, and nursery emersed plants switch to submersed leaves over a week or two. Wild in the southeastern US it is a common roadside-ditch and pond plant. It crosses freely with L. palustris, so many plants sold as one or the other are really the hybrid.
Outdoor pond use
- USDA zones
- 6–11 (winter low around -23°C or warmer)
Care notes
One of the easiest red-green stems, fine for beginners. Moderate to bright light, eight to ten hours, brings out the red-green gradient that makes it popular; in low light the red fades to olive and lower leaves may drop. It is one of the few reds that colour up even without CO2 under good light, though CO2 boosts both colour and growth. Iron is the key nutrient for the red, kept around 0.1 to 0.5 ppm, since iron shortage shows as white new leaves. Plant stems in groups of five to eight, trim the tops weekly and replant, and the cut lower stems branch into bushier growth. Growth is moderate to fast and nutrient needs are modest. Keep it around 20–28°C across a wide pH and hardness range. It is one of the best first red plants for anyone who wants colour without the fuss of Rotala or Alternanthera, since the natural gradient looks good without a perfect high-tech balance. It is an ornamental, not a crop, so it is unsuited to media-bed aquaponics or hydroponics.