Can I grow this in a regular garden bed?

No, it requires constant moisture and thrives best in shallow water or boggy conditions.

How deep should the water be?

It prefers shallow water up to 15 centimeters deep.

Plant guide

Bogbean.

Menyanthes trifoliata

Pronounced men-ee-AN-theez try-fo-lee-AY-tuh

Also known as Bogbean, Buckbean

The bogbean is a lovely aquatic perennial that thrives in shallow water or very damp, boggy soil. It features beautiful, fringed white flowers that look like they are covered in tiny snowflakes. It is a hardy plant that brings a natural, wild look to any pond or water garden.

Another photo of Bogbean — Photo by Tom Norton (CC BY) via iNaturalist

At a glance

Care level: Easy
Plant type: Aquatic perennial
Light: Full sun to partial shade
Indoor light: Bright indirect
Water: Every day
Mature size: 6 to 12 inches tall
Growth rate: Medium
Hardiness: USDA 3 to 7
Bloom time: Mid to late spring

Care

Keep the roots constantly submerged or in very saturated soil to mimic its natural wetland habitat. Watch for yellowing leaves which often signal that the water level has dropped too low. It is a very resilient plant that rarely needs much attention once established.

Watering: The soil must remain completely saturated or submerged at all times.
Feeding: Apply a slow release aquatic fertilizer tablet once in the spring.
Pruning: Trim back dead foliage in late autumn to keep the area tidy.
Repotting: Divide the creeping rhizomes every few years to prevent the plant from becoming overcrowded.
Soil: Heavy loam or aquatic soil
Soil pH: Acidic to neutral
Temperature: -35 to 25°C
Humidity: 60 to 100%
Drought tolerance: Low
Lifespan: Perennial, typically 5 to 10 years.
Fragrance: Light
Deer and rabbits: Moderate

Signs it needs repotting

Roots growing out of the pot
Reduced flowering
Crowded rhizomes

Safety

People: The leaves are considered toxic if ingested in large quantities due to the presence of gentianin.
Children: Keep children away from the foliage as ingestion can cause stomach upset.
Contact allergens: The sap may cause mild skin irritation in sensitive individuals.
Airborne allergens: Pollen is generally not considered a significant airborne allergen.
Edibility: The plant contains bitter alkaloids and should not be consumed without expert knowledge.

How to identify it

Three leaflets on each leaf stalk
Fringed white or pinkish flowers
Spikes of star shaped blooms
Thick creeping underground stems
Grows in shallow water or bogs

Height: 0.15 to 0.3m
Spread: 0.3 to 0.6m
Leaves: green, deciduous
Flowers: white, pink, 1 to 2cm
Fruit: brown, Late summer

Problems to watch for

By symptom

Plant problems by symptom

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Growing it

Propagation: division, seed
When to plant: spring
Overwintering: The plant goes dormant in winter. If in a container, ensure the roots do not freeze solid by sinking the pot deeper into the water.
In containers: It grows well in containers placed in shallow water, provided the pot is at least 20 centimeters wide.

Division

1. Lift the plant in spring.
2. Cut the rhizome into sections with buds.
3. Replant into wet soil or shallow water.

Group with other marginal aquatic plants to create a naturalistic pond edge.

Grows well with

Marsh Marigold · They share similar moisture requirements in pond margins.
Water Forget Me Not · It provides a nice color contrast in boggy areas.

Similar species

Buckbean · This is the same species.

Science

Family: Menyanthaceae
Genus: Menyanthes
Order: Asterales
Class: Magnoliopsida
Native range: Northern hemisphere wetlands.
Conservation: It is protected in some regions due to the loss of wetland habitats.

It acts as a pioneer species in wetland succession by trapping sediment with its creeping rhizomes.

Value to wildlife: nectar source
Pollinators: bees, butterflies
Uses: water gardens, bog gardens, wildlife ponds

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 1/9
Soil reaction: 5/9
Light: 7/9
Temperature: 3/9
Moisture: 9/9
Nutrients: 4/9

Taxonomy resolved against GBIF.

Questions people ask

Can I grow this in a regular garden bed?: No, it requires constant moisture and thrives best in shallow water or boggy conditions.
How deep should the water be?: It prefers shallow water up to 15 centimeters deep.

Where the name comes from

The name Menyanthes comes from Greek words meaning month and flower, possibly referring to the blooming period. Trifoliata refers to the three leaflets on each leaf.

Good to know

It is commonly known as bogbean.
The flowers have a unique fringed appearance.
It thrives in shallow water or very wet soil.
It is a circumpolar species found across the northern hemisphere.

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This guide was generated with AI on September 26, 2026 and checked against GBIF taxonomy. It is general information, not horticultural or veterinary advice. Read about how we build these guides.