In article , Klara
writes

I use wood-fire chimney soot in our organic growing system. It is
matured for several months before use, then liberally mixed with soil
before application. Much the same applies to garden bonfire ash.
Clinker and ash from solid fuel are used only for path wor

After the help on this thread, I've just put the wood ash into a
plastic bag and put it into the shed, to be used in the spring. Is that
what you mean by matured, or do I have to do something more
sophisticated?

Thanks!

Oops - I meant the soot ...

Yes to the ash or the soot. Either would be better kept in an open
container than in an airtight bag, so that they can 'breathe'.
--
Alan & Joan Gould - North Lincs.