Interested in our grow your own mushrooms workshops?


Learn About Growing Oyster Mushrooms

On Coffee Substrate

Here are the directions we use in our coffee cultivation workshops. 
  1. Add strained coffee grounds to your spawn cup and cover it with a paper towel
  2. Keep Adding Coffee grounds then transfer to a larger container (4 litres or so)
  3. It should remain whitish growth.  Watch for green mold contamination.
  4. Once your container is full and fully colonized, then cover it, and place in the fridge overnight.
  5. Bring it out of the fridge and cut 3 small 1” holes in the container.
  6. Select a Location in your house where you will pass by daily to monitor your kit’s progress
    1. Oyster mushrooms prefer temperatures ranging from ~10C-21C
    2. Avoid direct sunlight but indirect light is necessary
    3. Place the container on a plate or cookie tray to catch any dripping water
  7. Keep it Humid: Mushrooms need very high humidity to form
    1. To increase humidity, use a humidity tent and place it over top of the container
    2. A humidity tent can be a clear plastic bag with 10 or so quarter sized holes
    3. Mist 2-4 times daily to maintain condensation on the inside of the bag or tent
  8. Typically within two weeks a cluster of oyster mushrooms will emerge from container
  9. As the mushrooms grow, air exchange becomes increasingly important
    1. Not enough fresh air results in long stems and small mushroom caps
    2. Too much air exchange can cause them to dry out and abort because it’s harder to keep the humidity high
    3. Oyster Mushrooms like a lot of fresh air and some people find it helpful to prop up the bottom of the tent or completely remove it once the cluster is well formed (about the size of a golf ball) or when the caps start to expand
  10. When to Harvest: You will be enjoying your mushrooms within a week of seeing them begin to grow
    1. Oyster mushrooms are at their prime for eating when the cap has expanded but the outer edges are still slightly turned under
    2. If you let them over-mature, you will notice a dusting of white spores (mushroom “seeds”) on the plate or under your mushroom gills
  11. Harvest by twisting off the entire cluster, or cutting with a knife at the base. Cook them up fresh, or store in a paper bag in the refrigerator and eat within a week. 
  12. Always cook your mushrooms before eating
  13. Second Flush: After your first harvest, replace the humidity tent and continue to mist a few times daily and a second flush of mushrooms will soon grow from the original hole
  14. If no new mushrooms emerge within weeks, or you notice your kit has gotten very light, then it probably needs to be rehydrated
    1. Submerge the kit (bag and all) in cold non-chlorinated water for a few hours
    2. Drain off all the water and poke holes in the bottom as water left to pool inside the bag may cause bacteria to grow. 
    3. Place kit back under humidity tent and begin misting a few times daily until new mushrooms grow
  15. It may be possible to get a third flush, sometimes even a fourth flush
  16. Once no more mushrooms appear, it’s time to remove from bag and compost the kit
  17. The mushroom block is a super soil amendment in your garden!