Duckweed - Why Early Action is Essential

Duckweed may look harmless - even attractive - when it first appears as a sprinkling of tiny green leaves across the water. But left unchecked, this fast-spreading plant can quickly take over a pond, lake, or canal, causing serious problems for water health and biodiversity.

Why Tackle Duckweed Early?

Duckweed spreads rapidly, especially in warm, nutrient-rich water. A small patch can double in size in just a few days, quickly forming a thick, unbroken layer on the surface. This blanket blocks sunlight from reaching underwater plants and reduces oxygen levels, which can harm fish and other aquatic life.

By acting early, you can:

• Prevent it from smothering your waterbody.
• Reduce the time and cost of removal.
• Protect aquatic plants and wildlife.

Why Duckweed Can Be Difficult to Deal With

Due to its tiny size and ability to drift with the wind, duckweed can spread to every corner of a waterbody. Unlike larger aquatic weeds, it can’t simply be cut - it must be carefully removed from the surface without breaking it into smaller fragments.

At The Aqua Contractor, we use specialist mechanical equipment designed to sieve the water, lifting duckweed from the surface while minimising disturbance to the ecosystem.

How You Can Help Reduce Duckweed Growth

Duckweed thrives in nutrient-rich water, particularly where nitrogen and phosphorus levels are high. These nutrients often come from:

• Fertiliser runoff from nearby fields or gardens.
• Waste from livestock or waterfowl.
• Decaying organic matter such as fallen leaves.

To help limit duckweed proliferation:

• Monitor and manage nutrient levels in your waterbody.
• Reduce or avoid fertiliser use near the water’s edge.
• Install buffer strips of vegetation to filter runoff.
• Regularly remove fallen leaves and organic debris from the water.

These preventative steps won’t guarantee duckweed won’t appear, but they can slow its growth and make control easier.

The Importance of Ongoing Maintenance

Even after removal, duckweed can return from windblown seeds, waterfowl, or connected waterways. That’s why regular monitoring and maintenance are key to keeping it under control.

If you’ve spotted duckweed starting to spread, the sooner you act, the easier it will be to protect your waterbody.