One of my chosen roles in the European Botanic Gardens Consortium has been to champion the issue of invasive plants in our collections – and seed lists! We have developed a working list of known problem species across Europe. Some plants that we are still happily cultivating are fast becoming appalling weeds in continental Europe – Acer negundo, Akebia quinata, and Robinia pseudoacacia, to name just three. You may be loathe to cut down a handsome specimen, but the very least you should do is to label it as a problem plant. I was amazed on a recent trip to Finland to see Fallopia japonica proudly labelled without any hint as to its darker side.