Will weed killer destroy this plant, it is coming down a wall at the back of my garden and overtaking everything.
Yes it will but if the plant belongs to someone else, ie if it is growing in from someone else's garden, it will also cause criminal damage for which you could be prosecuted.
It is hard to know where it starts as it has travelled all along 8 gardens, last year it reached mine and next doors where there is a return brick wall so it will just carry on spreading and there is about 10 years growth on the garden next to me along with two other creepers. The wall is about 17' high so is difficult for me to get to the top.
Are we really talking about Lysimachia nummularia? I've struggled to get this established in a damp area of this garden - and it's supposed to love damp; it's sold as a pond marginal and for bog gardens.
I've put some of this in myself this year (thanks to a donation from a forumite) - the golden/yellow version is much less vigorous, and both types go much slower in shade.
Stick a small cutting of either in a container of water in the GH, however, and they develop roots within a day or so(!), so you could try creating a few more and blitzing it Dove.
Rob after three years it's getting the hang of things and is beginning to spread nicely around the shallow edges of the pond but certainly not rampant and I really can't imagine it running riot over eight gardens and growing over a wall
By the way - mine is the green version.
this wall is 17' tall. we can't be talking about creeping Jenny, Lysimachia nummularia. Could it be Virginia creeper?
could be it turns red in the autumn which is quite nice but still a pain