Easy to grow in any soil but prefers moist situations. To encourage flowering cut back stems after their second year. This plant is listed on Schedule 9 of The Wildlife (Northern Ireland) Order (1985), as amended, as an
invasive non-native species. While this does not prevent it from being sold or being grown in gardens in Northern Ireland, 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 in Northern Ireland 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