With clay pots I normally just tip out the gunk and refill. However this year in my manic cleaning episode I scrubbed all my clay pots and some plastic ones and all the greenhouse with a weak solution of jeyes fluid. That will be that for another 10 years or so (apart from the greenhouse - it is done yearly).
'Optimism is the faith that leads to achievement' - Helen Keller
Posts
Perhaps bulb-sellers might not be entirely unbiased with their advice