Open the Advanced Search

Various-leaved Pondweed

Potamogeton gramineus

Please keep in mind that it is illegal to uproot a plant without the landowner's consent and care should be taken at all times not to damage wild plants. Wild plants should never be picked for pleasure and some plants are protected by law.
For more information please download the BSBI Code of Conduct PDF document.


Plant Profile

Flowering Months:
Potamogetonaceae (Pondweed)
Life Cycle:
Maximum Size:
150 centimetres long
Ditches, gardens, ponds, water.

Green, 4 petals
A short, green flower spike. The stalks are thicker at the top.
The flowers develop into a dry seed, which is the fruit.
Narrowly oval (but very variable) floating leaves, up to 7cm long and 3.5cm wide. The submerged leaves are up to 9cm long and 12mm wide. Usually found growing in shallow acid water. Seldom seen in brackish water.
Other Names:
Grass-leaved Pondweed, Grassy Pondweed, Variableleaf Pondweed.
Frequency (UK):
Occasionally seen  

Similar Species

Other Information


Potamogeton gramineus, also known as grass-leaved pondweed, is a perennial aquatic plant that is native to North America. It is commonly found in freshwater ponds, lakes, rivers, and streams. The leaves are long, thin, and typically float on the water's surface, they are linear in shape, resembling those of grass and have smooth edges. The stems are long, thin, and anchored to the bottom by rhizomes. The flowers are small and inconspicuous, and arranged in spikes at the top of the stem. They typically bloom in late spring to early summer. It is an important food source for waterfowl and aquatic animals, and it also provides cover and habitat for fish and other aquatic organisms. It's considered a good oxygenator for the aquatic ecosystem and it's also used as an ornamental plant in water gardens and ponds.


Potamogeton gramineus, commonly known as Various-leaved Pondweed, is a species of aquatic plant that belongs to the family Potamogetonaceae. It is a submerged, perennial herb that is native to Europe, Asia, and North America, and is found growing in ponds, lakes, and slow-moving rivers.

The name Potamogeton gramineus comes from the Greek words "potamos" and "geiton," which mean "river neighbor." The specific epithet "gramineus" means "grass-like," referring to the plant's long, thin leaves that resemble blades of grass.

Various-leaved Pondweed has long, narrow, bright green leaves that are typically 3-6cm long and less than 1cm wide. The leaves are arranged alternately along the stem and have a distinctive, curved tip. The plant's stem can grow up to 1m long and is flexible, allowing the plant to sway with the current. The stem is also branched and can produce both male and female flowers.

The flowers of Various-leaved Pondweed are small and inconspicuous, and are arranged in dense, cylindrical spikes at the end of the stems. Male flowers are located near the top of the spike, while female flowers are found near the base. The plant reproduces through both sexual and asexual means, with the latter being achieved through the growth of rhizomes, or underground stems.

Various-leaved Pondweed provides important habitat and food for aquatic animals, such as fish, insects, and waterfowl. It is also a valuable plant for improving water quality, as it absorbs nutrients and pollutants from the water. However, in some areas, the plant can become invasive and form dense mats that outcompete native aquatic plants.

In traditional medicine, Various-leaved Pondweed has been used to treat a variety of ailments, including respiratory problems, skin conditions, and digestive issues. It contains a number of bioactive compounds, including flavonoids and phenolic acids, which may contribute to its medicinal properties.

Various-leaved Pondweed is a highly adaptable plant that can grow in a wide range of water conditions. It can tolerate both acidic and alkaline waters, and is found in both still and flowing water bodies. It is also capable of growing in both shallow and deep water, although it prefers water that is less than 3m deep.

One of the unique features of Various-leaved Pondweed is its ability to change the morphology of its leaves in response to water conditions. In shallow water, the plant produces narrow, ribbon-like leaves that are able to capture more sunlight. In deeper water, the plant produces broader, oval-shaped leaves that are more efficient at photosynthesis.

The plant is also able to survive in low light conditions, making it an ideal candidate for use in indoor aquariums. In fact, it is a popular aquarium plant due to its attractive appearance and ease of care.

Despite its ecological importance, Various-leaved Pondweed is threatened by a number of factors, including habitat destruction, water pollution, and invasive species. In some areas, the plant is intentionally removed due to concerns about its invasiveness. However, when managed properly, it can provide important benefits to aquatic ecosystems and the organisms that depend on them.

In addition to its ecological and medicinal value, Various-leaved Pondweed has also been used for food and fodder in some cultures. Its young leaves and stems can be consumed raw or cooked, and the plant has been used to feed livestock in certain regions.

Various-leaved Pondweed plays a crucial role in the nutrient cycling of aquatic ecosystems. The plant absorbs nutrients, such as nitrogen and phosphorus, from the water column, which can help to reduce algal blooms and improve water clarity. The plant also provides a habitat for a wide variety of aquatic animals, including small fish, insects, and snails.

In addition to its ecological importance, Various-leaved Pondweed has cultural significance in some Indigenous communities. For example, in certain Indigenous cultures in North America, the plant is used in traditional medicine to treat a variety of ailments, including respiratory problems, fever, and stomach issues.

Distribution Map

Reproduced by kind permission of the BSBI.

Click to open an Interactive Map