On Thu, 10 Jan 2019 13:39:20 +0000, Chris Green wrote:

You can't really "stop this happening again", gravel (or similar)
drives need maintenance and 'stuff like soil' will always build up
over time.

Yep. Just tell your gardener to keep it clear. They'll just have to
regulary hand weed it(*) or rake it.

(*) or every time a weed becomes big enough to pull, pull it.

--
Cheers
Dave.