weed killer?

[jujuman]

Until recently my rear garden was a jungle including lions monkeys and a couple of elephants, I have now hacked down most of it and I want to cover part of it with Cotswold stone approx 70m2 but I want to put down some kind of plant killer that will be permanent, taking in to consideration the garden was over run with brambles so I have no idea how big the roots are. A friend suggested using building lime but the bloody weeds seem to thrive on it. Any suggestions will be appreciated

[Farley3Toes]

sodium chlorite.....I believe that the recommentation is to not plant anything on ground treated with this for at least a year and NEVER plant anything edible. It's very strong stuff.

[jujuman]

Thank you Farley3T's I will give it try