Mould growing in a dry area
I've got a fairly large closet that I use as storage. I have things like tools, golf bag, luggage, sporting equipment, etc. in there. I also use it to store wine bottles, both unopened and empty. I've noticed some of my things like my golf bag, luggage (both kind of a cordura type fabric) and some wooden table legs are covered in white mould spores. I noticed the mould on the luggage at the end of last year, but didn't see it anywhere else, so I just cleaned the luggage, but now it's come back. I have 4 pieces of luggage all side by side and the mould is only growing on one piece.
It's only on certain items, and I've emptied the closet and crawled around on the carpet and touched the walls and everything is bone dry. Even the items that are covered in mould are dry.
Why is this growing? How do I stop it?
Thanks for your help.