No, it is a free floating aquatic plant that absorbs nutrients directly from the water.

No, it will not harm adult fish, but its traps can catch small prey like daphnia, mosquito larvae and newly hatched fish fry, so it is best kept out of fry tanks.

Plant guide

Greater bladderwort.

Utricularia vulgaris

Pronounced yoo-trik-yoo-LAIR-ee-uh vul-GAIR-iss

Also known as Greater Bladderwort, common bladderwort

Utricularia vulgaris — Photo by Ellyne Geurts (CC0) via gbif

This fascinating aquatic plant is a rootless, free floating carnivorous species. It captures tiny organisms using specialized bladders on its submerged stems. You will find it thriving in calm, nutrient poor waters like ponds and marshes.

At a glance

Care level: Moderate
Plant type: Aquatic carnivorous plant
Light: Full sun to partial shade
Indoor light: Bright indirect
Water: Every 0 days
Mature size: 30 to 100 centimeters
Growth rate: Fast
Hardiness: USDA 4 to 9
Bloom time: Late spring to mid summer

Care

Keep this plant in a container with plenty of stagnant or slow moving water. Watch for algae buildup, which can smother the plant and block its light. Ensure the water remains nutrient poor to keep the plant healthy.

Watering: Always keep the plant fully submerged in water.
Feeding: Do not fertilize, as this plant captures its own nutrients from prey.
Pruning: Trim back excess growth if the plant begins to crowd its container.
Repotting: Repotting is not applicable since it is a free floating aquatic plant.
Soil: None, free floating
Soil pH: 5.0 to 7.0
Temperature: 0 to 30°C
Humidity: 70 to 100%
Drought tolerance: Low
Lifespan: Perennial, typically 3 to 5 years in stable conditions.
Deer and rabbits: High

Signs it needs repotting

The container becomes overcrowded with plant mass.
Water quality begins to decline due to excessive biomass.

Safety

People: There is no evidence of toxicity to humans, but it is not a food source.
Children: Keep this plant away from small children as it requires standing water which poses a drowning risk.
Contact allergens: There are no known skin irritants associated with this plant.
Airborne allergens: The pollen is not considered a significant airborne allergen.
Edibility: This plant is not intended for human consumption.

How to identify it

Finely divided, feathery submerged leaves
Small, hollow bladders on stems
Yellow, snapdragon like flowers
Lacks true roots
Forms dense, floating mats

Height: 0.05 to 0.2m
Spread: 0.3 to 1m
Leaves: bright green, deciduous
Flowers: yellow, 1 to 2cm
Fruit: brown, late summer

Problems to watch for

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Growing it

Propagation: division, seed, turions
When to plant: spring
Overwintering: In cold climates, the plant will form turions that sink to the bottom of the pond. Leave these undisturbed until spring when they will naturally rise to the surface.
In containers: It is perfectly suited for containers, provided you use a pond or bowl with at least 10 liters of water.

Division

1. Gently pull a section of the plant away from the main mass.
2. Place the cutting into a new container of clean, stagnant water.
3. Ensure the container receives bright, indirect sunlight.

Ensure the water remains clear of excessive algae to allow enough light for the bladder traps to function.

Grows well with

Water Lily · They share similar water requirements and provide complementary foliage textures.
Hornwort · Both are free floating plants that help oxygenate the water.

Similar species

Lesser Bladderwort · A smaller relative with similar growth habits.

Science

Family: Lentibulariaceae
Genus: Utricularia
Order: Lamiales
Class: Magnoliopsida
Native range: Widespread across temperate regions of Europe and Asia.
Conservation: It is not currently listed as endangered, but it is sensitive to water pollution and habitat loss.

It thrives in nutrient poor, still, or slow moving water where its carnivorous habit provides a competitive advantage.

Value to wildlife: nectar source
Pollinators: bees
Uses: ornamental pond plant, natural mosquito control

Through the year

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Flowering

Fruiting

Foliage

Ecological indicators

Salinity: 1/9
Soil reaction: 5/9
Light: 7/9
Temperature: 5/9
Moisture: 9/9
Nutrients: 2/9

Taxonomy resolved against GBIF.

Questions people ask

Does it need soil?: No, it is a free floating aquatic plant that absorbs nutrients directly from the water.
Will it eat my fish?: No, it will not harm adult fish, but its traps can catch small prey like daphnia, mosquito larvae and newly hatched fish fry, so it is best kept out of fry tanks.

Where the name comes from

The name Utricularia comes from the Latin word utriculus, meaning little bottle, referring to the bladder traps. The species name vulgaris simply means common.

Good to know

It is a rootless aquatic plant that floats freely in the water.
The traps are among the fastest moving structures in the plant kingdom.
It produces winter buds called turions that sink to the bottom to survive cold weather.

Also in

Deer-resistant plants

Keep your greater bladderwort growing

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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.