Fine-leaved water-dropwort (Oenanthe aquatica) care guide

Group
Plants
Other names
Fine-leaved water-dropwort, Water fennel, Phellandrium aquaticum
Family
Apiaceae (carrot family)
Origin
Europe from Ireland to central Siberia and from southern Scandinavia to the Mediterranean
Water
freshwater
Maximum size
150 cm
Temperature
4–22°C
pH
6.5–8
Care level
expert
Lighting
High light; CO2 helpful

Care

Fine-leaved water-dropwort is a native European wetland herb of reed swamps, ditches, canals and pools with changing water levels. Above water it grows to about 1.5 m with hollow stems and finely divided leaves; underwater it makes very fine, thread-like leaflets. It flowers with white umbels in summer. Caution: it is toxic. The fruits are known to cause poisoning, and it is easily confused with hemlock water-dropwort, which is far more dangerous. Wear gloves and keep it away from children and pets. The sources do not describe its use in aquaria. It is a temperate marsh plant suited to coldwater tanks and the margins of wildlife ponds, and is likely to struggle in heated tanks. It usually lives one to a few years. Water figures are our estimate, not from the sources. Sources: Wikipedia (en.wikipedia.org/wiki/Oenantheaquatica); Wikipedia, List of freshwater aquarium plant species. Checked October 2026.

Breeding

Wikipedia says it spreads entirely by seed (up to 40,000 per plant); stems may also root at submerged nodes, so cuttings can be tried.

Compatibility and tank mates

Toxic plant; best kept in ponds or coldwater set-ups with hardy native fish. Not suited to tropical tanks.

Last updated 8 October 2026. Community-edited care guide on Aquatic-Auctions.

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