Eleocharis sp. 'Mini' (mini hairgrass) care

Light

Eleocharis sp. 'Mini' 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 PAR (around 50-80 PAR at substrate) to carpet densely; under low light it grows leggy, pale and patchy. In an aquarium use a strong planted-tank LED for 7-9 hours daily. A phone lux-meter at the leaf surface should read 1,500-3,000 lux at noon.

Watering

Water eleocharis sp. 'mini' fully submerged; 30-50% aquarium 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 aquatic species kept permanently underwater. Maintain stable, clean water; weekly partial changes keep nitrate and organics low so the fine blades stay clear of algae.

Soil and pot

Eleocharis sp. 'Mini' grows best in nutrient-rich aquatic substrate. Roots best in fine, nutrient-rich planted-aquarium soil (aqua soil) 3-5 cm deep. Inert gravel or sand works only with root tabs to feed the dense runner network. 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

Eleocharis sp. 'Mini' sits happiest at around 100% (submersed) humidity and 20-28°C (68-82°F). As a submersed aquatic, humidity is not a factor underwater. The emersed (out-of-water) farmed form needs near-saturated humidity to survive until converted to its submersed leaves. If you keep the room above 20 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 eleocharis sp. 'mini' sparingly. Dose a comprehensive liquid aquatic fertiliser (macro + micro) with the water column and push root tabs into the substrate every few weeks. CO2 injection dramatically improves carpet density and speed. 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 eleocharis sp. 'mini' in the Growli community. Each is annotated with the most common cause so you know where to start.

• Patchy or leggy growth — Almost always too little light or no CO2 — raise PAR and add CO2 injection to force a dense, low carpet rather than thin straggly blades.
• Algae on blades — Fine blades trap thread and spot algae when nutrients are imbalanced or flow is poor; keep CO2/light/ferts in balance and improve circulation.
• Slow melt after planting — Emersed-grown tissue often dies back as the plant converts to submersed form; trim melted tops and be patient while new underwater blades emerge.
• Carpet lifting off substrate — Insufficient root anchorage or being uprooted by fish; plant small portions deep and let runners knit in before heavy maintenance.

Propagation

Divide the mat or separate individual runner plantlets and replant in small clumps; under good light and CO2 they quickly send out new runners to fill gaps. 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

Eleocharis sp. 'Mini' is mildly toxic to pets. Eleocharis is not individually listed by the ASPCA Toxic/Non-Toxic Plant database, and no genus-level ruling exists, so its pet status is unconfirmed. Treat with caution and verify with a vet; do not assume pet-safe. As a fully submerged aquarium plant, realistic ingestion exposure is low. 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.

Eleocharis sp. 'Mini' deep-dive guides

Every aspect of eleocharis sp. 'mini' care, each with its own calibrated guide:

• Eleocharis sp. 'Mini' watering schedule
• Eleocharis sp. 'Mini' light requirements
• Best soil mix for eleocharis sp. 'mini'
• Eleocharis sp. 'Mini' fertilizing guide
• When to repot eleocharis sp. 'mini'
• How to propagate eleocharis sp. 'mini'
• Eleocharis sp. 'Mini' growth rate & size
• Eleocharis sp. 'Mini' cold hardiness
• Eleocharis sp. 'Mini' temperature & humidity
• Is eleocharis sp. 'mini' toxic to cats & dogs?
• Is eleocharis sp. 'mini' toxic to cats?
• Is eleocharis sp. 'mini' toxic to dogs?

Featured in these plant shortlists

Eleocharis sp. 'Mini' qualifies for 2 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 small & tabletop houseplants — Compact houseplants that stay under about 40 cm — desk, shelf and windowsill plants that never outgrow a small space.
• Browse all 29 plant shortlists — pet-safe, low-light, drought-tolerant and more

Related guides

Eleocharis sp. 'Mini' is also commonly called mini hairgrass or micro hairgrass.

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