David in Normandy wrote:
It is very invasive. The best solution I've found is to grow it in an
old plastic bucket (with cracks/small holes in the bottom so it can
drain). The bucket isn't buried at all. There is always a plentiful
supply to pick.

Yeah, I think it was 'just planted' when we moved in. Never been able to
get rid of it. I got rid of it out of the original patch, but it's just
spread, including into the lawn.

We've finally managed to get rid of it from the herb border, but it has
been a chore, it comes back from the tiniest bit of root.

Bit like artichokes, but shorter. ;-)