You never really do! I found the best way is to dig it up and making sure you get rid of every bit of root then be vigilant and every time you see a bit spray it with weed killer or dig it out again. I have learnt to live with some as my neighbours have it, but you can reduce it and keep it under control.

Patience is the key !!

dig out by hand ver carefully. then check very week for signs of growth. then pick it out as you see it. took me two years but got it done eventually.

you could also paint it with round up. I have used a pastry brush before as it gives good coverage.

This works for me too SBG but the neighbours both sides let it grow so I get it back again all down the fences.

that is so unfair Drc. have you tried that rigid plastic sheeting [lawn edging strip] to see if it stops it?

I have a wooden grip board under the fencing SBG and it seems to come under it