Potamogeton Natans (Broad Leaved Pondweed)

Broad Leaved Pondweed | Potamogeton natans

A UK native pondweed with broad floating leaves, submerged growth and small summer flower spikes, ideal for wildlife ponds, natural ponds and larger planted water features.

Native floating and submerged pond plant for wildlife cover, natural planting and pond balance

Broad Leaved Pondweed, botanically known as Potamogeton natans, is a native aquatic pond plant grown for its floating oval leaves, submerged stems and excellent wildlife value. It is a useful choice for wildlife ponds, natural ponds, larger garden ponds and planted water features where a native pondweed is wanted to create habitat both at and below the water surface.

The floating leaves are broad, oval and leathery, usually green to brownish green, and can reach around 6 cm to 10 cm long. These leaves sit on the water surface and create natural cover, helping to shade parts of the pond and provide resting places for small aquatic insects. Below the surface, the plant produces long stems and narrower submerged growth, which provides cover for fish fry, tadpoles, newts and aquatic invertebrates.

Potamogeton natans is often sold as an oxygenating plant, although it is slightly different from fine leaved oxygenators such as Hornwort, Water Milfoil or Elodea. Its submerged growth helps support pond balance by photosynthesising below the water when enough light reaches the plant. The floating leaves also add visual interest, making it a good choice where you want a more natural, native pond look rather than a purely ornamental display.

In summer, Broad Leaved Pondweed can produce small, greenish flower spikes that rise above the water surface. The flowers are not showy, but they add natural seasonal interest and help give the pond a more established wetland appearance.

This plant can be introduced as weighted bunches, but it will usually establish better if planted into aquatic soil, heavy loam or pond substrate. If used in a lined or fibreglass pond, it should be planted in an aquatic basket or planting crate rather than loose in the base. Once established, it can grow into deeper water where light levels are suitable, with a possible depth range of around 30 cm to 1.5 m initially and deeper in clear ponds.

Broad Leaved Pondweed is native, but it can grow strongly and may become difficult to manage in natural ponds, lakes or very large water bodies. It should never be released into the wild or into connected waterways. In garden ponds, remove surplus growth when needed and dispose of it responsibly away from streams, rivers, ditches and natural ponds.

Key benefits

• UK native aquatic pond plant

• Broad floating leaves give natural surface cover

• Submerged stems provide underwater habitat

• Useful for wildlife ponds and natural ponds

• Provides shelter for fish fry, tadpoles, newts and invertebrates

• Small flower spikes rise above the water in summer

• Helps support pond balance as part of a planted pond

• Can grow in deeper water once established

• Suitable for larger ponds and naturalistic planting schemes

• Can be dropped in as weighted bunches

• Establishes better when planted into aquatic soil

• Good alternative to purely ornamental floating plants

Reasons to buy Broad Leaved Pondweed

Broad Leaved Pondweed is a great choice if you want a native pond plant that looks natural and provides habitat at several levels of the pond. The floating leaves give surface cover, while the submerged stems create underwater structure for pond life.

It is especially useful in wildlife ponds where natural cover is important. Newts, tadpoles, fish fry, insects and other aquatic creatures benefit from plants that create shelter below the water surface.

This plant also gives a very authentic pond appearance. The broad floating leaves and small flower spikes look far more natural than many decorative pond plants, making it ideal for wildlife gardens, native planting schemes and informal ponds.

For best results, plant it where it can be managed. It is better suited to medium and larger ponds than very small container ponds, as it can grow strongly once established.

Care instructions

Place Broad Leaved Pondweed in a sunny to partially shaded pond position where light can reach the submerged growth. Good underwater light helps the plant establish and photosynthesise properly.

The recommended starting depth is around 30 cm. Once established, it may be moved or allowed to grow deeper, up to around 1.5 m or more where the water is clear enough for light to reach the plant.

Weighted bunches can be dropped into the pond, but planting into aquatic soil, heavy garden loam or aquatic compost will usually improve establishment.

In lined or fibreglass ponds, plant into an aquatic basket or planting crate. This helps contain the roots and makes future thinning easier.

Remove excess growth if the plant spreads beyond the area you want it to cover. This is particularly important in smaller ponds or ponds where open water needs to be maintained.

Never dispose of unwanted pond plants into the wild. Remove surplus growth and compost it safely away from natural waterways, or dispose of it responsibly.

Avoid using in ponds that overflow or connect directly to ditches, streams, rivers or lakes.

Flowering period

Broad Leaved Pondweed can produce small greenish flower spikes in summer, usually from around June to September depending on conditions.

The flowers rise above the water surface but are not brightly coloured. This plant is mainly grown for its floating leaves, submerged growth and wildlife value.

Flowering may vary depending on pond depth, light levels, water quality, maturity and seasonal weather.

Size, spread and growing conditions

Botanical name: Potamogeton natans

Common name: Broad Leaved Pondweed, Floating Pondweed

Plant type: Native submerged and floating leaved aquatic pond plant

Floating leaf size: Usually around 6 cm to 10 cm long

Stem length: Can extend through the water column depending on depth

Growth rate: Medium to fast once established

Flower colour: Small greenish flower spikes

Flowering period: Summer, usually June to September

Position: Full sun to partial shade

Recommended starting depth: Around 30 cm

General planting depth: 30 cm to 1.5 m

Possible established depth: Can grow deeper in clear ponds where light reaches the plant

Soil: Aquatic soil, heavy loam, pond substrate or planting crates

Native status: Native to GB and Ireland

Use note: Native but can be vigorous. Manage growth and do not release into wild watercourses.

Best suited for: Wildlife ponds, natural ponds, larger garden ponds and planted water features

Wildlife value: Provides surface cover and underwater shelter for fish fry, tadpoles, newts, aquatic insects and invertebrates

How many bunches will I need?

As a useful starting guide, allow approximately 3 bunches per square metre of pond surface area.

For example:

• 1 m² pond area: approximately 3 bunches

• 2 m² pond area: approximately 6 bunches

• 4 m² pond area: approximately 12 bunches

This is only a guide. The right amount will depend on pond size, depth, light levels, water clarity and how quickly you want planting to establish.

For smaller ponds, start with fewer bunches and thin growth as required.

Oxygenating and submerged plant guidance

Broad Leaved Pondweed is best treated as a submerged and floating leaved pond plant rather than a standard fine leaved oxygenator.

Only underwater growth photosynthesises below the surface and contributes oxygen directly into the water during daylight. The floating leaves provide surface cover, shade and habitat.

Planting depth is a guide only. Start new plants shallow enough to receive good light, then allow them to establish before moving them deeper.

Regular thinning may be needed if growth becomes dense. Removing surplus growth also helps prevent too much old plant material breaking down in the pond.

Your plant on arrival

Broad Leaved Pondweed may arrive as weighted bunches or as potted aquatic plants, depending on the size and availability.

Weighted bunches can be placed directly into the pond, although they often establish better if planted into aquatic soil or a small planting crate.

If supplied as a potted plant, place it at the recommended depth or pot it on into a larger aquatic basket if more growing room is needed.

Plant size, leaf colour, stem length and growth form will vary depending on season and growing conditions. This is normal for living aquatic plants.

Dispatching your pond plants

Pond plants are carefully selected, packed and dispatched to help them arrive in good condition. As living aquatic plants, Broad Leaved Pondweed can vary in colour, leaf size, stem length and density depending on the season, weather and natural growth cycle.

Unpack your plants promptly when they arrive. Keep them wet at all times and introduce them to the pond as soon as practical.

Do not leave Potamogeton natans exposed to sun, wind or drying conditions. If you cannot place it into the pond immediately, keep it in a container of pond water in a cool, shaded position for a short period.

For best establishment, start in shallower water with good light before allowing the plant to spread into deeper suitable areas.

Explore more oxygenating pond plants or browse our complete pond plants range.