Water starwort

Callitriche palustris

Also known as Vernal water-starwort, Spiny water starwort, Narrow-fruited water starwort

FreshwaterStemCuttingsDivision

Water starwort (Callitriche palustris) — Gower · CC BY-SA 4.0

Care at a glance

Light: High light
CO2: No CO₂ needed
Temperature: 41–72°F; 5–22°C
Max height: 11.8 in; 30 cm

Growth rate: Medium
Placement: Midground
Type: Stem
pH: 6.0–7.5
Hardness: 2–15 dGH
Spread: 3.1 in (8 cm)
Nutrient uptake: Root + water column
Growth region: Submersed or emersed
Difficulty: Medium
Family: Plantaginaceae
Origin: Native to ponds, ditches, and slow, cool waters across temperate North America and Eurasia.

Overview

Water starwort is a midground stem plant for a cool, well-lit tank, rated medium in difficulty. It suits coldwater and biotope aquariums more than warm tropical tanks.

Did you know

Water starwort's small leaves gather into floating, star-shaped rosettes at the surface. That is where the common name starwort comes from.

Caring for water starwort

Strip the lower leaves of water starwort and push the stems into the substrate a little apart. It belongs in the midground of a cool tank.

It needs bright light but no added CO2. Keep the water cool, at 41 to 72°F (5 to 22°C), with a pH of 6 to 7.5. It feeds through both roots and leaves, so root tabs plus a liquid fertilizer cover it.

It grows at a medium pace to about 12 in (30 cm). Cut it back in spring to keep it in check, and replant the cut tops. A large clump can also be split and planted as smaller ones. In weak light the stems stretch and drop their lower leaves.

Good to know

Water starwort is now placed in the plantain family, Plantaginaceae, though it was long treated in its own family, Callitrichaceae. It is a hydroannual and completes its life cycle within a single year. Its slender, trailing stems carry small, spoon-shaped leaves, and underwater it makes soft, pale green tufts. Its tiny flowers are among the simplest of any flowering plant.

In the wild

Water starwort is native to ponds, ditches and still or slow, cool waters across temperate North America and Eurasia.

Common questions

Does water starwort need to be planted in the substrate?

Yes. Strip the leaves from the lower part of each stem, then push the stems into the substrate one at a time, a little apart.

Does water starwort need CO2?

No. Water starwort grows well without added CO2.

How much light does water starwort need?

Water starwort needs high light from a strong planted-tank LED. In weaker light its stems stretch and drop their lower leaves.

Does water starwort need root tabs?

They help. Water starwort takes nutrients through both its roots and its leaves. Root tabs near its roots and a liquid fertilizer cover both.

How do you propagate water starwort?

Water starwort propagates by cuttings and division. Cut off the top of a stem and replant it, and the stump left behind grows new shoots. Split a large clump into smaller ones and plant them separately.