I have acquired a load of old used mushroom compost and don’t know which areas of my garden it is ok to use in or what ratio to soil to use it? I have raised beds, spuds area, greenhouse, fruit trees and ornamental garden
If it is not very well rotted, it tends to make cabbage and other leafy vegetables very leafy if over-used and can give carrots an earthy taste.
But if very well rotted, this is not a problem. It is too rich for fruit trees, and good for flowers if the soil is a bit light or lacking in nutrients.