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[Tzabaoth]

I grew mushrooms for a while and have a great appetite for them.  Harvesting spores from freshly picked mushrooms is pretty easy, but finding the right medium has been my issue.  I'd like to use recycled or, using the current yuppy term, upcycled media.  I like the idea of being able to reuse coffee grounds but don't know how successful it is.  Anyone have any thoughts?

http://www.growveg.com/growblogpost.aspx?id=261

Thanks,

.: Tzabaoth

1 Like Sunshine likes this.

[TBM]

I've had success with adding some used coffee grounds into the substrate mix when I've grown Shiitake in the past, but I've never attempted using only used coffee grounds before (I've grown with rice, sawdust, straw/poo, tiny amount of gypsum, etc.). I found that when I mixed in ~10% coffee grounds it sped up growth slightly and the mycelia looked more healthy as well (never tried more than 10%). It sounds worth giving it a try Nice find!

[Saros]

I had pretty good results growing Oysters on just torn up cardboard boxes mixed with shredded straw... 

Although they'll grow and fruit on just cardboard and paper, I'm a little wary of eating them because I don't know what sort of chemicals were in the ink/toner, or left over goo from tape. Doesn't sound too appetizing to me.... But since they grow readily on these maybe there's another use.. Perhaps you could just use it as a sort of fungal shredder for junk mail, and in turn it will generate CO2 for your botanicals:)

I second using coffee grounds as well. Though I don't drink enough coffee to use much of it in my substrates..

However, if you're looking for a source for coffee grounds, try your local coffee shop. A while back I asked for spent coffee grounds at a Starbucks (for this purpose) and they gave me a huge garbage bag full of them:) This was long before I knew what I was doing when it came to growing mushrooms so they unfortunately ended up going to waste

[isaak]

If you're looking into growing with cardboard and used coffee grounds I highly recommend Jame Weiser's talk from Telluride 2013.

He describes a method of 'cold pasteurization' in which he leaves the cardboard submerged in a bucket of water for approximately 10 days. During this time, aerobic microorganisms (the main competitors of the fungi we're trying to grow) essentially drown and anaerobic microorganisms then proliferate and consume the dead aerobic organisms.

James describes the dynamics of fungi: once a food source is found, the mycelium first aims to surround it completely to prevent competitors getting a foot-hold. The mycelium then grows through the surrounded food source. Once a food source is surrounded it is almost impossible for contaminants to proliferate. His method for growing with cardboard and coffee takes advantage of mycelial growth dynamics by layering cardboard and coffee, with inoculated grains strategically placed to help ensure mycelial dominance.

I think this is an extremely simple method of growing and conducting small-scale mycoremediation (just think of how much cardboard and used coffee grounds get thrown away!). Plus, it's an easy way to get people growing mushrooms

I'll be doing experiments with this method over the next couple months and will post as I go.

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[happyconcacti]

I've grown Oysters on 100% pure coffee grounds from a local coffee shop.

It was only O.K. for the beginning then contammed heavily.

I had a 5 gallon bucket that was about 2/3 full of grounds. I "steam-pasteurized" the coffee grounds in a covered steamer setup. It was really messy but smelled great.

With pure coffee grounds, it seemed too compact of a medium to be successful: the mycelium run was slow and spotty, both of which are bad. And it never quite reached the center of the bucket.

If I did the coffee ground method again, I'd definitely add something to keep it more aerated, like bark or wood chips. 

[TBM]

What method did you use to inoculate the coffee grounds? That's over 3 gallons of coffee grounds you're talking about, if not inoculated properly it would contaminate every time. With something like that much coffee you'd probably be better off starting the mycelia in a jar using the PF tek, then once that's fully colonized you would crumble it up and mix it into the substrate.... either that or maybe trying a liquid culture inoculation?

I must agree though coffee can easily compact and mycelia does need proper aeration, do you think it would matter which type of tree the bark/wood chips came from?

[Saros]

I wonder if the ph of the grounds would be much of an issue. I'm sure it depends on strain somewhat as to what's acceptable. I believe the ph of coffee is around 5.5 and I try shoot for a ph around 7.5 in my substrates. It would be interesting to compare growth on ph adjusted grounds and non ph adjusted grounds. Might need to go make some coffee....

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