By definition, mushrooms are fungi, and therefore will grow in any type of environment that contains waste. This includes compost, coffee grounds, manure, sawdust, and even paper. Therefore, growing mushrooms in regular garden soil is not possible, and so we'll show you how to grow mushrooms in coffee grounds. We've chosen coffee grounds because it's obviously more sanitary than other waste and it won't stink up your growing area.
How to Grow Mushrooms in Coffee Grounds – a DIY Guide
- Used coffee grounds
- Mushroom spawn with sawdust (oyster or shiitake)
- A bucket or container of 2 to 5 gallon in size
- Spray bottle
Fill a bucket or container with coffee grounds (used). Don't fill up all the way, leave a little bit of space. Grab a marker or pen and mark up to where the coffee grounds reach. Dump the coffee grounds out and place them in a bag.
Drill a few holes around the bucket, half way between the line you drew and the bucket rim. These holes are used to release CO2, since you'll be later covering the top of the bucket with plastic film.
Fill your bucket up with coffee grounds again. Break the mushroom spawn with sawdust into the bucket and mix with some coffee grounds so that they are spread out over the top inch layer.
Cover your bucket with a layer of cellophane and poke a few holes in the top of the cellophane. This will keep the mushrooms in a moist environment and also let some air out.
Keep the bucket in a dark corner of your home.
Remove the cellophane cover once a day and spray the coffee grounds with a little bit of water. Cover back up when finished.
Care and Harvest:
- After 15-20 days, you will start to see white patches form on the top layer of the coffee grounds.
- Once this happens, just remove the cellophane and move the bucket to a sunnier spot in your home. Be sure that the temperature is the same.
- Spray the top of the layer with water twice a day.
- Within a week or so, you'll start seeing small mushrooms emerge.
- A few days after that, the mushrooms will grow nice and fleshy, their caps will turn upwards, and you can harvest them.
Warning: If you use mold starting to form on the mushrooms, spray with less water and move to a cooler location.
Now that you know how to grow mushrooms in coffee grounds, it's time to roll up your sleeves and get to planting!