What Can You Do With Spent Fruiting Blocks?

Even after your mushroom fruiting blocks have produced a few flushes, they can still be used to grow more mushrooms with just a little care. Once you’ve harvested your mushrooms, simply break up the spent block into smaller pieces and place them into a new container or patch of fresh growing medium, like straw, sawdust, or compost. By doing this, you’re providing the mycelium with more space to continue colonizing and fruiting.

Spent mushroom substrate can also be put to great use in your garden or mulch beds. The nutrient-rich material is full of organic matter that can improve soil quality and water retention. You can mix the spent substrate into garden beds or spread it as mulch around plants. Over time, it will break down, enriching the soil with nutrients while promoting healthy plant growth. Additionally, the mycelium in the spent substrate can continue to break down organic matter, supporting the development of beneficial fungi in your garden.

How to Prepare Fruiting Block

To prepare your mushroom fruiting block for fruiting, make a 6-8 inch cut along the side of the bag, and place the block in a humid area of your home, such as the kitchen near a sink, where the moisture will help encourage healthy mushroom growth. Once you harvest your first flush, turn the bag around and cut again. The block will flush several times, with slightly smaller flushes each time.