On 21/06/2019 10:45, newshound wrote:
On 21/06/2019 10:17, Roger Mills wrote:
I have a patio area/path consisting of a couple of inches of pea
gravel on top of some weed matting.

When I first created this 20-odd years ago, I gave the soil a liberal
dose of sodium chlorate before laying the weed matting. This kept it
weed-free for quite a few years, but the matting has now deteriorated
- allowing a lot of weeds to take root.

I have removed the gravel and the weeds, and am about to take up the
matting and renew it before covering it with new gravel. I need to be
able to neutralise the soil in order to prevent any roots or seeds
left in from growing. I don't think you can buy sodium chlorate any
more. Most of the weedkillers available seem to be of the systemic
type - which kill existing weeds but don't affect the soil. But that's
not what I want!

Any bright ideas?

Salt?

Which I would probably apply as the largest available granules, maybe
lightly forked/raked in, rather than by "watering". To provide a sort of
slow release.