"Nick Maclaren" wrote
..
My current rosemary and thyme problems are root rot. The soil may
be free-draining, but that doesn't help if the wet doesn't let up,
and is combined with occasional moderate frosts (-5 or more).

Try growing it in a biggish pot (with decent holes in the bottom) of free
draining (John Innes + gravel) and let it root through the pot into the
ground.

--
Regards
Bob Hobden
17mls W. of London.UK