Can I grow this in a regular garden bed?

Only if the soil stays constantly wet, as it will wilt quickly in dry conditions.

Does it need full sun?

It prefers full sun to partial shade.

Plant guide

Marsh pennywort.

Hydrocotyle vulgaris

Pronounced hy-dro-KOT-ih-lee vul-GAIR-iss

Also known as Marsh Pennywort

Marsh Pennywort — Photo by anonymous (CC BY-SA) via iNaturalist

This charming aquatic perennial thrives in damp, boggy areas and shallow water. It features small, circular leaves that look like tiny umbrellas floating on the surface. It is a lovely choice for pond edges or water gardens.

Another photo of marsh pennywort — Photo by Barry Stewart (CC BY) via gbif

At a glance

Care level: Easy
Plant type: Aquatic perennial
Light: Full sun to partial shade
Indoor light: Bright indirect
Water: Every 1 to 2 days
Mature size: 4 to 8 inches tall
Growth rate: Fast
Hardiness: USDA 5 to 9
Bloom time: Mid to late summer

Care

Keep the soil consistently saturated or submerge the plant in shallow water to mimic its natural wetland habitat. Watch for yellowing leaves, which often signal that the plant is drying out too much. It spreads quickly, so you might need to contain it if you have a small space.

Watering: The soil must remain constantly wet or submerged.
Feeding: Apply a balanced aquatic plant fertilizer during the active growing season.
Pruning: Trim back the stems if the plant starts to crowd out other species.
Repotting: Repot when the plant becomes root bound or outgrows its container.
Soil: Wet, boggy, or aquatic soil
Soil pH: 6.0 to 7.5
Temperature: -25 to 30°C
Humidity: 60 to 100%
Drought tolerance: Low
Lifespan: Perennial, typically 3 to 5 years
Deer and rabbits: Moderate

Signs it needs repotting

Roots growing out of the drainage holes
The plant looks crowded in its container

Safety

People: It is generally considered non-toxic, but ingestion is not recommended as it may cause stomach upset.
Children: The plant is not dangerous, but keep an eye on toddlers near water features where it grows.
Edibility: This plant is not considered edible and should be avoided.

How to identify it

Circular leaves with scalloped edges
Leaves attached at the center
Creeping stems along the ground
Tiny clusters of greenish flowers

Height: 0.05 to 0.2m
Spread: 0.3 to 1m
Leaves: bright green, evergreen
Flowers: white, pale pink, 0.2 to 0.5cm

Problems to watch for

Aphids · Small insects that may cluster on the stems during dry spells.

By symptom

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Growing it

Propagation: division, seed
When to plant: spring, summer
Overwintering: It is hardy and will remain green in mild winters, though it may die back in colder regions. Simply leave it in place and it will regrow from the roots in spring.
In containers: It grows beautifully in containers submerged in shallow water or kept in very wet soil.

Division

1. Carefully lift a clump of the plant from the mud.
2. Gently pull the creeping stems apart to separate into smaller pieces.
3. Replant the pieces immediately into wet soil or shallow water.

Group this with other moisture-loving plants to create a lush, boggy display.

Grows well with

Marsh Marigold · They both thrive in the same wet, boggy conditions.
Water Mint · It provides a nice textural contrast to the round leaves.

Similar species

Floating Pennywort · It is a larger, more aggressive relative that can become invasive.

Science

Family: Araliaceae
Genus: Hydrocotyle
Order: Apiales
Class: Magnoliopsida
Native range: Europe and North Africa.
Conservation: It is common in its native range and not of conservation concern.

It grows in wet, marshy habitats where it uses its creeping stems to colonize muddy banks.

Value to wildlife: provides cover for small aquatic life, stabilizes muddy pond edges
Pollinators: bees, beetles
Uses: groundcover for bog gardens, pond edge filler, aquatic container plant

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 1/9
Soil reaction: 5/9
Light: 6/9
Temperature: 5/9
Moisture: 9/9
Nutrients: 5/9

Taxonomy resolved against GBIF.

Questions people ask

Can I grow this in a regular garden bed?: Only if the soil stays constantly wet, as it will wilt quickly in dry conditions.
Does it need full sun?: It prefers full sun to partial shade.

Where the name comes from

The genus name Hydrocotyle comes from the Greek words for water and cup, referring to the leaf shape. The species name vulgaris simply means common.

Good to know

It is often called pennywort because of its round, coin-shaped leaves.
It spreads rapidly by creeping stems called stolons.
It thrives in waterlogged soil where other plants might struggle.

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This guide was generated with AI on October 19, 2026 and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.