Almost impossible, sorry, but there it is.
These will help:
Spray off every late June (before they 'flower') with a parquat based herbicide which will burn them off.
Pull them at the same time if you don't like chemicals.
If in cultivated ground, dig as deep as possible and dig out shoots which will regrow (they will).
If you don't need the ground, cover with an old carpet, black plastic weighed, or similar and leave for a year.