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Shropshire, United Kingdom

Mushroom compost good as soil improver? My regular supplier of soil improver or ‘black velvet’ as we just to call it has retired. I have now been offered mushroom compost but am not sure if that would be good to scatter over perennial borders this winter to improve soil. Understand it should not go near ericaceous loving plants but not sure of its overall benefits? Any thoughts? Thanks



well it is often suggested as a good soil improver and as it is used to be made from horse manure I can see why. not sure what modern mushroom compost is made from.

it will add bulk and additional humus to the soil so wont do any harm. not sure about ericaceous plants though.

30 Oct, 2020


We used to use it when we lived near a Mushroom place(now sadly defunct and built over). Definitely not to be used near lime haters as it is very alkaline. We also got a really good crop of mushrooms from it as well. Good for a clay soil as it does help it to flocculate.

30 Oct, 2020


Thanks for your replies, will have a think.

30 Oct, 2020


I used it way back, horse manure time, worked well plus the odd mushroom as a bonus

Soil round here is alkaline anyway so not a problem

31 Oct, 2020


I was always under the impression that spent mushroom compost was alkaline as it contains Gypsum which is added to 'sweeten' the compost. But on a previous question, Tugbrethil reminded me that the addition of Gypsum did not change the alkalinity of the compost and I looked up the chemical formula and he was dead right.

1 Nov, 2020


We often use spent mushroom compost to condition the soil, here in the desert, and it works very well. It even slowly reduces the pH, which is a benefit here, but might become a problem in parts of the UK, I suppose.

1 Nov, 2020


I believe that soils in your area generally tend to be poor? If so I'd gladly accept any sort of compost.You can always check the pH later if you suspect it might have changed a bit.

1 Nov, 2020

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