In article ,
the_constructor wrote:

I purchased a bag of compost earlier on this year and have used some of it
to start cuttings off in the house and also to repot some African violets.

The problem that I have is that ontop of the compost, it has gone mouldy.
The plants are thriving but the compost is mouldy. I only water from the
bottom.

Could someone please advise what I am doing wrong or what could be causing
the mould.

You are doing nothing wrong, and it's almost certainly harmless,
so ignore it. Mould is ubiquitous, and composts are often not
fully decomposed before use, so moulds grow readily on them.
In general (not always), moulds will harm growing plants only
when they are already in trouble from some other cause (e.g.
too cold and too damp, or whatever).


Regards,
Nick Maclaren.