Ludwigia palustris (marsh purslane) care

Light

Ludwigia palustris is what florists mean by "bright spot, no direct sun" — close enough to a south or east window to feel the brightness, with a sheer curtain or a few feet of distance keeping the sun off the leaves. Needs high light to develop red and bronze tones; under low light it stays plain green and grows leggy. In an aquarium provide 0.5W/L or strong LED for 8 hours daily. A phone lux-meter at the leaf surface should read 1,500-3,000 lux at noon.

Watering

Water ludwigia palustris kept fully submersed or in saturated substrate; in aquaria do a 30-50% water change weekly. The actual day count varies with pot size, light, and season — the finger test (or lifting the pot to feel its weight) is more reliable than a fixed calendar. Empty any drainage saucer afterwards so the pot isn't sitting in water. An obligate wetland plant grown in water or constantly waterlogged soil. Soft to moderately hard water, pH 6.0-7.5. CO2 injection sharply boosts growth, colour and density but is not essential.

Soil and pot

Ludwigia palustris grows best in nutrient-rich aquatic substrate. Thrives in fine aquasoil or sand capped over nutrient base; benefits from root tabs as it is a heavy root feeder. Emersed, use a peaty, constantly wet loam in a bog or pond margin. A pot with a working drainage hole is non-negotiable for this species — even free-draining mix will turn soggy in a closed planter. If you love the look of a decorative pot without a hole, use it as a cachepot around an inner nursery pot you can lift out to water.

Humidity and temperature

Ludwigia palustris sits happiest at around 80-100% humidity and 18-28°C (64-82°F). Emersed growth demands near-saturated air in a covered tank, paludarium or bog; submersed growth is unaffected by room humidity. If you keep the room above 18 year-round and avoid placing the plant near a cold draught, a hot radiator, or an air-conditioning vent, you have already handled the two biggest indoor stressors.

Fertilising

Feed ludwigia palustris sparingly. In planted tanks dose a full liquid macro/micro fertiliser regime plus substrate root tabs every few weeks; iron-rich dosing intensifies red colouration. Emersed plants need only a wet, fertile substrate. Skip fertiliser entirely on a stressed, recently-repotted, or actively wilting plant — fertiliser salts make damage worse, not better. Wait for a round of healthy new growth before resuming a feeding rhythm.

Common problems

Below are the issues we see most often on ludwigia palustris in the Growli community. Each is annotated with the most common cause so you know where to start.

• Lower stems go bare — Caused by insufficient light reaching the base or shading from taller plants. Trim tops and replant them, and thin dense growth so light penetrates.
• Green instead of red — Red and bronze tones only develop under high light and good iron levels. Increase intensity and dose an iron-rich fertiliser.
• Melt after planting — Submersed-grown plants may shed emersed-form leaves when conditions change. Keep parameters stable; new submerged leaves emerge within a couple of weeks.
• Stunted, twisted tips — Usually a micronutrient or CO2 deficiency. Add CO2 or improve flow and ensure complete trace-element dosing.

Propagation

Cut healthy stem tops 8-12 cm long and replant them in the substrate; each cutting roots at the nodes within days. Side-shoots can also be separated. Propagation is the cheapest, most satisfying way to expand a collection — and it doubles as insurance against losing a mature plant to an accident. Take a backup cutting once the parent is established and healthy.

Toxicity to pets

Ludwigia palustris is mildly toxic to pets. Ludwigia is not individually listed on the ASPCA toxic or non-toxic plant database, so a definitive pet-safety rating cannot be given; treat with caution and verify with a vet. As an aquatic plant it is not a typical browsing hazard, but ingestion of any quantity could cause mild gastrointestinal upset. If you keep cats, dogs, or curious children in the house, weigh placement carefully — a high shelf or a hanging planter is enough for casual safety. For severe ingestion incidents, call your local vet and the ASPCA Animal Poison Control Center (in the US, 888-426-4435).

Pet-safety status is sourced from the ASPCA Toxic and Non-Toxic Plant List, which catalogues the most-asked-about plants for cats, dogs, and horses.

Ludwigia palustris deep-dive guides

Every aspect of ludwigia palustris care, each with its own calibrated guide:

• Ludwigia palustris watering schedule
• Ludwigia palustris light requirements
• Best soil mix for ludwigia palustris
• Ludwigia palustris fertilizing guide
• When to repot ludwigia palustris
• How to propagate ludwigia palustris
• Ludwigia palustris growth rate & size
• Ludwigia palustris cold hardiness
• Ludwigia palustris temperature & humidity
• Is ludwigia palustris toxic to cats & dogs?
• Is ludwigia palustris toxic to cats?
• Is ludwigia palustris toxic to dogs?

Featured in these plant shortlists

Ludwigia palustris qualifies for 3 curated Growli shortlists — each one filtered objectively from our structured plant-care library, so the selection is consistent and checkable:

• Best plants for a north-facing window — Houseplants for a north-facing window: bright, even, indirect light and no scorching direct sun. Each pick verified against its documented light needs.
• Best humidity-loving houseplants — Houseplants that thrive in a bathroom, kitchen, or by a humidifier — selected by documented humidity preference.
• Best fast-growing houseplants — Houseplants documented as fast or vigorous growers — quick to fill a pot, cover a pole or trail down a shelf.
• Browse all 29 plant shortlists — pet-safe, low-light, drought-tolerant and more

Related guides

Ludwigia palustris is also commonly called marsh purslane or water purslane.

• Monstera care — light, water and common problems
• Pothos care — light, water and common problems
• Fiddle leaf fig care — light, water and common problems
• All 5561 plant care guides in the Growli library