Hairy jointgrass, Joint-head grass, Jointhead arthraxon, Small carp grass, Creek grass
Family
Poaceae (grass family)
Origin
East Asia and Australia; invasive in the Americas
Water
freshwater
Maximum size
60 cm
Temperature
10–28°C
pH
6–7.5
Hardness
Tolerant (estimate)
Care level
expert
Lighting
Full sun, emersed
Care
Warning: this is a land (or at most bog) plant, not a true aquarium plant. Kept fully underwater it slowly weakens and dies, so it is best grown emersed in a paludarium, or with only its roots in the water. Small carpetgrass (family Poaceae) is an annual grass of moist, sunny ground such as riverbanks, wetlands and floodplains in East Asia and Australia. It grows 30–60 cm tall with heart-based, hairy-edged leaves 2.5–7.5 cm long and roots where stems touch the ground. Wikipedia says nothing about aquarium use. It is an annual land grass, so it will not last as a submerged plant. Water figures are our estimate, not from the sources. It is invasive in the United States (found in at least 25 states and banned in Connecticut and New York) and in Central and South America. Never release this plant or dispose of it in drains or waterways; it is invasive in some countries. Sources: Wikipedia (en.wikipedia.org/wiki/Arthraxonhispidus); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.
Breeding
An annual grass that spreads by seed and by rooting at stem nodes.
Compatibility and tank mates
Do not sell or buy it as a true aquarium plant; it belongs in a paludarium, bog garden or damp border.
Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.
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