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Day 29: Growing Mushrooms From Used Coffee Grounds


Mushroom Mycelium Contaminated With Green Mold

I stopped adding to this jar once I saw the green mold.  It started small and spread rapidly to this point only after about 5 days.  This jar is on day 29.  I'm saving it to use in a video where I'll scoop out the insides and see what we find.

Here's another photo:

Mushroom Mycelium Contaminated With Green Mold

Now for my other jars:

Mushroom Spawn Jar Using Coffee Grounds

The jar on the right is day 29, Middle jar is on day 18 or 19, the jar on the left is day 14 and going very slow.  That one had the new strain that I didn't have a very good stem butt to start with.  Also it may be contaminated but I'm not sure yet.  I'm very careful when I add more grounds and use plenty of alcohol.  The green mold spores are in the air all around us so they are very easily contaminated.  I even soak the coffee filter before I open the jar. 

Here's another shot:

Mushroom Spawn Jar Using Coffee Grounds

I grind my own coffee beans and have been making the grounds not so fine so that more air space is in the jar.  I just filled that jar on the left to the top today.  I figure it will be ready in a week.

Sumi over on Facebook posted his progress.  His look fantastic and growing FAST!  See Below:

Mushroom mycelium

I didn't have my good camera today so sorry if my photos are not the best.  I'll post one more photo update and then the next video in about 10 days.


Day 8 here and I don't see much activity. I think there is some extra white on the surface of the coffee and mushroom stem ends but nothing that I can see on the sides of the jar. Have you opened your 29 day jar yet or are you just leaving it alone. To bad about the green stuff but it will be interesting to se if it makes any difference. Your latest one seems to racing right along. 

SleestaksRule's picture

I haven't opened the day 29 green mold jar but I just added more coffee to the good 29 day jar.  Sumi said he was keeping his in the dark.  I'm going to put mine in the dark a few days and see it I see a difference.  Make sure yours doesn't dry out since it's taking a while.  This has been fun and something I'll keep doing.  I hope yours take off.

I think I will put mine in the dark too. 

Emmett_Grogan_Lives's picture

Do you have any plans on growing Shiitake?

Hardwood sawdust and chips...



Miles of smiles...

No I plan to try a shiitake log, ordered the plugs last week.

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