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Cellar mould

Hi all,

I was wondering if anyone knew about cellaring conditions went it comes to mould growth in cellars. I’ve been in crypts before in wineries but i haven’t seen anything like this. It’s like a white crystally fur carpet.

Should i be worried or is it only helping? We keep our wine in it and it wasn’t there when we started storing it. Over the past year it’s grown like that over the whole floor and ceiling

It looks really crystalline, just did a quick Google, have you checked it’s not efflorescence?


Thanks @Brocklehurstj emergency over, apparently (according to my partner’s father) he had someone in to check it and it is just the minerals being leached up but it’s harmless :slight_smile:


Looks very much like efflorescence to me. Try rubbing some of the white stuff between your fingers - if it is efflorescence it will feel like salt crystals ('cos that is what efflorescence is!) / if it is a mould it will be soft and woolly in texture.
Efflorescence is caused by dampness coming through the brickwork and leaching out salts which then crystallise as the water evaporates. If you have only recently started using the cellar and have increased the ventilation this is the most likely cause of efflorescence. This phenomenon is often seen on the outside of new brick buildings. A stiff brush will remove the crystals but you will probably have to repeat this at intervals.
A mould is a different problem altogether!


Are those tiles or bricks?

If you can shift your wine somewhere short-term, then I was told by a plasterer to lift the covering (in this case tiles), put Bitumen on the surface underneath, replace tiles. It stops the damp that creates the salts from coming out.

I have tried it by the way, and it did work. The only bit that continues to effloresce is the bit I missed :smiley:


Thank you @DavidTheChemist yes very much the salt not the mould, it just scared the heebeejeebees out of me haha! As long as it doesn’t threaten the wine stash!


Have you measured the humidity in your cellar? If it’s around the 70% mark, should be ok.

Another vote for salts leaching out from brick/ mortar/ general damp. Might indicate a damp (condensation) problem if localised? possible worth checking that ventilation bricks haven’t been covered up/ overgrown.

As far as I know, cellar mould is black and furry - ages ago I went around Martell’s cellars in Cognac - soft sooty black mould, including all the eves OUTSIDE !


I’d be wary about putting in something impermeable. That moisture in the soil has to go somewhere. Old cellars are supposed to breath, so by blocking moisture in one part you will transfer it somewhere else.

If it is salt crystals on the wall, applying whitewash/lime wash will allow the walls to breathe whilst keeping things tidy.


I agree about it being effloresence and I certainly wouldn’t try blocking it up either. i have lived in houses with Victorian cellars until a couple of years ago and the wine was never adversely affected.

Ahhh thanks @KateMH that’s in fact very reassuring to hear. It will only be there for a few months as we’ve just moved to another place with a cellar so we can get it out for then.