Was headed out camping and walked by my coffee grounds bucket, and was shocked by what I saw!
This what the project looked like in April.
I had been around this area earlier in the week and didn’t notice anything!
Beautiful luxurious Oyster Mushrooms! They are growing quite well, and I can’t wait to eat them. This marks a growing success for me, because this was the Oyster growing project I was most interested in.
Tons and tons of coffee grounds are wasted in our landfills each year. This proves that food can be produced using this waste product. Not only does it keep this valuable resource out of our landfills, but the mushrooms also neutralize the caffeine in the grounds.
Once again the process was low cost and not labor intensive. The spawn was just simply mixed into the coffee grounds and left to grow on it’s own. I can see a real use for these mushrooms in poor countries with shortages of food, and plenty of waste.
Thanks again to Wild Joe’s for the organic coffee grounds, and Garden City Fungi for the spawn.
16 thoughts on “Oyster Mushrooms On Coffee Grounds”
This is the best use of a waste product I have ever seen. Especially when there is plenty of coffee ground waste in America . Wonderful invention can go a long way contributing to malnutrition. Thank You
Thank you, and yes I agree! I could not stand for organic coffee grounds to be thrown away. The next step will be to grow reishi and shiitake on the coffee grounds. An added bonus is the mushrooms eat the caffeine and keep it out of our water.
Pls email instructions on how to prepare coffee grounds before adding spawn or liquid culture to coffee grounds.
Thank you for your response!
Coffee grounds don’t need any preparation for inoculation. Fresh out of the coffee maker, they are moist and pasteurized. When they come to room temperature, you can add the spawn. It gets trickier when they mold, which they do very quickly. Since they are pasteurized, they are a perfect environment for mold, as well as spawn. I have inoculated moldy coffee grounds, and they flushed with oyster mushrooms. Oyster spawn is very aggressive and it overtook the mold. Otherwise you would have to pasteurize or sterilize the coffee grounds. This would be way to expensive and messy for production. One way to keep your coffee grounds from getting moldy is to keep them frozen until you are ready to inoculate. There is quite a bit about oysters growing on coffee grounds on the site under oysters or coffee grounds. Let us know how you do,
I have an oyster farm and hatchery. I am getting too old to tram about in the water and never did get muck out of the hatchery and rather than quitting and going bankrupt I have new people coming in to take it over, The hatchery equipment is being moved to a new location and I have an empty building. Can’t sell oyster in the summer months and idea ! Grow oyster mushrooms in there. Then it be a REAL Oyster farm. Oysters on the half shell and Oyster Mushrooms too. Good idea or just mental meandering of a geriatric oyster farmer gone mad??
Hello David and thanks for your comment!
Oyster mushrooms are a great choice to start with. They grow on almost anything and are aggressive. The only disadvantage is they don’t have a very long shelf life. Drying the excess would be a partial solution.
“Good idea or just mental meandering of a geriatric oyster farmer gone mad??” Your asking me? I think it is a great idea, but my sanity has been questioned many times! Let us know how you do,
David- we’re thinking the same too!
Thanks for the information on preparing the coffee grounds- just what I needed! 🙂 What do you think to mixing a few woodshavings (a couple of handfuls) in too- might help aerate?
Great article 🙂 I found it really useful.
Please help with these three doubts regarding growing mushrooms on coffee grounds:
1. If I ask for coffee grounds from the vendors at the end of the day, will the grounds may have contaminated after being exposed for the whole day?
2. Do I thoroughly mix the coffee grounds and spawn or just let spawn sit at the top of the substrate?
3. Can I sterilize the polythene bag in which I am growing mushrooms using alcohol or will I have to boil it? I fear that alcohol might kill the spawn too.
Hi Jo, and welcome to Montana Mushrooms!
Mushrooms seem to love a matrix. I would use fresh cut wood chips because old ones will have spores already in them. let us know how you do,
Hi Pranshu, and welcome to Montana Mushrooms!
1. Day old grounds are great as long as the containers are kept clean.
2. I usually put the spawn on top and mix it in a little.
3.I don’t use alcohol for the reason you mentioned.
Let us know how you do,
I haven’t grown mushrooms yet but am planning to do it soon. Will let you know how it goes. Thanks for the advice 🙂
How to pasteurize coffee grounds?
Hi Vanessa, and Welcome to Montana Mushrooms!
I would try a hot water bath method. You could use a basket with a screen, or I have always wanted to try putting the grounds in burlap bags and and pasteurizing the whole bag! Another possibility would be to use biodegradable dish soap or a diluted hydrogen peroxide rinse.
If you can get them right away, the humans have rinsed and pasteurized them for you!
Let us know how you do,
Just take them out of the freezer 24 hours before you are going to use them so they thaw and get to room temperature.
Great growing tip! I freeze my coffee grounds until I need them also.