Needle hairgrass
Eleocharis acicularis
Also known as Tall hairgrass, Needle spikerush, Eleocharis acicularis 'Mini' (cultivar)
Care at a glance
- Light
- Medium light
- CO2
- CO₂ beneficial
- Growth rate
- Medium
- Placement
- Foreground
- Type
- Carpeting
- Temperature
- 59–79°F (15–26°C)
- pH
- 5.5–7.5
- Hardness
- 1–14 dGH
- Max height
- 7.9 in (20 cm)
- Spread
- 5.9 in (15 cm)
- Nutrient uptake
- Root + water column
- Growth region
- Submersed or emersed
- Difficulty
- Easy
- Origin
- Near-global (Europe, Asia, North America)
- Family
- Cyperaceae
Overview
A grassy carpeter that spreads aggressively by underground runners to form a lawn. Plant small bunches of a few blades each, spaced out, and let the runners fill the gaps over several weeks. Bright light keeps it growing horizontally and dense; in low light it stretches tall and thin and the carpet opens up. CO2 is not required but roughly doubles the speed of filling in. Trim the lawn with scissors to a uniform height to keep it tidy and encourage thickening.
In the wild
An almost globally distributed spikerush found across Europe, Asia, and North America in ponds, ditches, lake margins, and slow rivers. It grows both submersed and emersed and is hardy enough to overwinter outdoors in temperate climates. Tolerates a wide range of water from soft to fairly hard.
Good to know
A true sedge in the family Cyperaceae, related to other Eleocharis spikerushes used in the hobby such as E. parvula and E. montevidensis. The thin green blades are not leaves but photosynthetic stems (culms); the true leaves are reduced to sheaths at the base. This species, sometimes called the taller acicularis form, reaches greater height than the smaller dwarf and 'Mini' selections.
Did you know
Did you know mowing a hairgrass carpet short with scissors actually thickens it, because each cut blade triggers the plant to push out more runners and new shoots.
Where to buy
Some links may not be the exact species or variety.
- Aquarium Co-Op Live plants and dependable gear for community tanks
- Aquarium Plants Factory Aquatic plants shipped from a California greenhouse
…or ask your local fish store.
Appears in
Growing Needle hairgrass?
Track your planted tank, set reminders and plan your layout.
Related plants
Dwarf hairgrass
Eleocharis parvulaMedium lightForeground3.9 in (10 cm)
Giant hairgrass
Eleocharis montevidensisMedium lightMidground11.8 in (30 cm)
Umbrella hairgrass
Eleocharis viviparaMedium lightBackground15.7 in (40 cm)
Cyperus helferi
Cyperus helferiMedium lightMidground11.8 in (30 cm)
Common nardoo
Marsilea drummondiiMedium lightForeground4.7 in (12 cm)
Marsilea quadrifolia
Marsilea quadrifoliaMedium lightForeground4.7 in (12 cm)