Canadian pondweed

This plant is listed on Schedule 9 of the UK Wildlife and Countryside Act as an invasive, non-native species. While this does not prevent it from being sold in the UK, or from being grown in gardens, the RHS encourages those that do grow it to take great care with managing it and with disposing of unwanted material. The RHS also encourages gardeners to find alternative plants to grow to those listed on Schedule 9. For suggested alternative plants see the Plantlife/RHS guide: Gardening without harmful invasive plants

Spreads by stem fragments; all plants in the UK are female