Hello everyone, never posted here before but I sure hope I can get some
help.

I have a patch in my garden which I would dearly like to kill everything
off--plants, shrubs and grass--since I will be placing clay bricks in
this position in 2 months. Can anyone tell me what chemical/s I could
use to permanently kill every living plant in this area?

Many thanks in advance.

PS I've tried salt, it has worked but not as well as I had hoped for.
Weed killer has also worked on the smallish plants and grasses, but the
bigger plants seem to be resisting it.