The Ludwigia Care Guide: How to Grow Red Stem Plants

Ludwigia is the genus most planted-tank keepers reach for when they want red without committing to a high-tech setup. These stem plants shift through shades of red, pink, copper and burgundy depending on how much light you give them, and several species will hold usable color in tanks running no CO2 at all.

Ludwigia Care at a Glance

• Light: Medium to high. Low light produces green growth, not red.
• CO2: Not required for growth; recommended for full color.
• Difficulty: Beginner (Repens, Palustris) to Intermediate (Senegalensis, sp. White).
• Placement: Midground to background.
• Mature height: Roughly 6–16 inches depending on species.
• Temperature: 68–82°F. pH: 6.0–7.5.
• Feeding: Root and water column. Responds strongly to iron.
• Propagation: Stem cuttings.

How Do You Make Ludwigia Turn Red?

Red pigmentation in Ludwigia is a light response, not a fixed trait of the plant. The same stem that grows olive-green in a low-light corner will turn deep red directly under a strong fixture. If your Ludwigia is staying green, light intensity is the first and usually only variable worth changing.

Three factors drive color, in order of impact:

1. Light intensity. Medium-to-high light is the threshold where most Ludwigia species begin showing red rather than green.
2. Iron and micronutrients. Anthocyanin production depends on available iron. Pale or yellowing new growth alongside poor color almost always means a micronutrient shortfall.
3. Nitrate restraint. Very high nitrate levels push plants toward green vegetative growth. Moderate nitrate tends to produce better red expression.

CO2 accelerates all of this but is not strictly required — Ludwigia repens will color up in a well-lit low-tech tank, just more slowly and with less saturation than in an injected one.

How Do You Plant and Trim Ludwigia?

Plant stems individually about two inches apart, burying only the bottom node or two and stripping any leaves that would sit below the substrate line. Planting a whole bunch as one clump is the most common early mistake — the inner stems get shaded, rot at the base, and the bunch thins out from the inside.

Trim by cutting just above a node. The cut stem branches into two new shoots, so regular trimming is what converts a row of single stems into a dense bush. Replant the trimmed tops directly into the substrate; they root within one to two weeks.

Which Ludwigia Species Should You Choose?

Beginner-friendly

Ludwigia repens is the standard entry point — fast, tolerant of a wide light range, and red-tinged even in moderate conditions. Ludwigia palustris 'Green' is the same easy profile without the red requirement.

Intermediate color varieties

Ludwigia Super Red Mini stays compact with the most consistent red of the common varieties. Ludwigia Rubin (sold as Red Diamond) and Ludwigia glandulosa (Peruensis) lean burgundy and bronze rather than true red.

Advanced and collector varieties

Ludwigia senegalensis and Ludwigia sp. White produce pink-and-cream veined patterning unlike anything else in the genus, but both demand high light and CO2 to hold form. Ludwigia sp. 'Pantanal' is covered in its own Pantanal care guide.

How Do You Propagate Ludwigia?

Cut a healthy top section four to six inches long, just below a node, and replant it in the substrate. The parent stem branches below the cut and continues growing. Because every trim yields a plantable cutting, a single bunch of six stems typically fills a background row within two to three trim cycles — roughly two months under good light.

Ludwigia Problems and Fixes

Staying green instead of turning red. Insufficient light in nearly every case. Raise intensity or extend photoperiod, and confirm taller neighbors aren't shading the stems.

Leggy stems with wide gaps between leaf nodes. Also a light problem. Trim back hard and replant the tops closer to the light source.

Lower leaves dropping while tops look healthy. Normal stem-plant behavior as the plant redirects energy upward. Harvest and replant the healthy tops rather than trying to rescue the base.

Melting in the first one to two weeks. Expected when a plant converts from emersed nursery growth to submersed growth. Trim the melted leaves; submersed growth follows.

Pale or yellow new growth. Iron or micronutrient deficiency. A comprehensive liquid fertilizer usually corrects it within two weeks.

Where to Start

Ludwigia Repens is the most forgiving way into the genus. Every Ludwigia we ship is grown hydroponically in our California greenhouse rather than imported, which means stems arrive already adapted to nutrient-rich growing conditions and free of snails and pest algae.

Keep Reading

• The Alternanthera Care Guide — the other major red genus that performs without CO2.
• Best Red Aquarium Plants — how Ludwigia compares to Rotala and Alternanthera for color.
• The Myriophyllum Care Guide — pair Ludwigia's color with fine feathery texture.