"Colin" wrote in message
After recent and past bonfires, I have collected the ash & charcoal
for use
on the garden.

However, as there is no label on the side, I am unsure of how best
to apply
it - is it best done in spring, or should it be put on all the way
through
season?

Does anyone have any ideas?

I am talking about relatively small quantities, I have a carrier bag
full, &
I guess application rate would be a scattering of a few handfuls per
m^2

Use it in spring in the same way that you would dolomite or lime to
sweeten soil.