Hi is this to kill of plants like grass celandines etc? if it is then any contact weedkiller such as roundup would do. this can accidently get on the woody parts of a shrub/hedge without doing any damage. avoid spraying on the hedge foliage though.

welcome to GoY

There is a product by roundup that u just dab on the leaves of the weeds and it kills this down to the root. Whether or not it works well is another question x

Depending on the weeds you might find Weedol works - its intended for lawn weeds but lots of those are the same as hedge weeds. Just keep it off the hedge leaves.

The Glyphosate stick for dabbing on leaves does work, but doing a whole hedge bottom would take ages!

I used Roundup extra strong the one in the black plastic container. I sprayed all under my hedge that had tons of ivy. Got rid of it all and the hedge is fine.