Dreaded weed

A couple of years ago I dug up a path made of old bricks and the adjoining raspberry patch down to the clay so as to purge [as I thought] every single trace of weed that had infested my allotment from the adjoining plot & playing field hedge that harbors a host of species of weed. One of them is "Columbine" - the dreaded pest with the white trumpet type flower - but it (along with nettles and wild blackberry plants) has surfaced again amongst the raspberries & blackberry plants. I suppose there is no quick remedy for this cursed weed and wondered if "Verdona" - the very effective systemic killer of weeds like Dandelions - would filter back into the root system if I doused the stem of a shoot with it or maybe submerged one in a shallow tray of the liquid? To halt the spread beyond where it has reached I thought about putting some old roof slates on end along the side of the path but wondered if the craft roots might creep past them even if overlapped". Has anyone else a better mode of attack to solve this irksome problem? Second question; My last year's crop of onions has kept sound till recently when they began to sprout new growth thus making them no good to eat, is there any way of preventing this from happening please. (see 2nd pic) Cheers Dave.

 

A thousand thanks will look up that link. Regards Dave.

 

I believe that an effective method of application of glyphosphate (the active ingredient in systemic weedkillers) is to put a bit in a polythene bag along with some bindweed foliage. Crushing the foliage is a good idea too. The logic is that the crushed stems allow the glyphosphate to enter more easily, and by securing the bag with a rubber band and then leaving for a week, the glyphosphate is in contact with the foliage for a very long time - even if it rains.

It worked for me.