What's wrong with spent mushroom compost?

Do you buy spent mushroom compost? Do you know what’s in it?

It’s Peat Free April and while we await the outcome of the 10-minute bill in parliament next week, I thought I would write about spent mushroom compost – a favourite soil improver.

Spent mushroom compost – it’s light, easy to work with, full of nutrients, free of weeds and disease, rich in organic matter so improves soil structure and water retention. This soil improver is also reasonably priced with a one tonne bulk bag costing around £80-100. So, what’s not to like about spent mushroom compost? One word: PEAT.  

Many of my gardening friends who have avoided peat over many years were horrified to learn that virtually all spent mushroom compost (SMC) contains between 10 and 15% peat. It’s a favourite of many a gardener and landscaper and why wouldn’t it be so, give this type of description: “Mushroom compost is one of our best selling products and highly recommended by many of the top names in horticulture as an excellent soil conditioner, mulch and planting compost. Mushroom compost is…