Can You Reuse Mushroom Substrate?

Can you reuse spent mushroom substrate to grow more mushrooms on? I've have read you can, especially between mushroom species. So I thought I would trial it between two mushrooms varieties within the same family. Doing so could increase mushroom farming yields against the substrate volume used.

I used pink oyster mushroom substrate which has already grown around 1.5kg of mushrooms. I re-hydrated the substrate, sterilized it, inoculated it with Phoenix Oyster, and grew a bunch of mushrooms which weighted 650g.

Starting out with around 1.9kg of dry matter, I grew MORE than 1.9kg of mushrooms, giving myself a estimated biological efficiency over 100%.

This wasn't a scientific study by any stretch, and I am not claiming all substrate should be reused. The flush from this was small and of a lower quality. That being said, my humidifier had broken, and we were experiencing hot and dry weather.

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Steamer Blueprint! Get this built and but the accessories listed. I use it to sterilize up to 300kg of substrate at a time! ♨️♨️♨️

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Want to try growing mushrooms? Start with this mushroom growing kit!

The following literature is great to learn how to grow mushrooms

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Want to Grow Mushrooms? Checkout these handy items below!

Substrate Preparation

Fruiting room essentials

Incubation/lab essentials

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[OakandSpore]

Want to know how much income you can make farming mushrooms? Check it out here ->

[gardenlifelove]

Growing mushrooms is decomposing on large scale. You basically are making super compost each time you grow mushrooms. When you do the multiple grows using different species, then you're adding all kinds of good organic matter to the soil from the mushrooms as well as the wood fibers breaking down into cellulose and carbon. Awesome video and great educational content!

[tedward]

Page 337 in the Growing Gourmet and Medicinal Mushrooms book. Going to attempt growing on spent blocks over the winter. Thanks for the videos and sharing so much information!

[AwninGod]

They turn the used substrate into compost here in Texas. Fruit trees love it (especially my avocados) A small cone shaped mushroom that grows in my planter boxes have a symbiotic relationship with my trees. Grew an avocado to 12' in a 24" diameter pot with a weeping bucket design.

[fishmut]

Recycle, recycle, recycle mate, well done, absolutely if you can reuse the blocks it makes sense to do that with a lot less waist and at the end when it’s no longer viable to use anymore you got a fantastic mushroom compost if you like to bag up and sell as well to gardeners, that’s what I would do if In Your situation or maybe even use for worm farms bedding, I’m sure worms would love to convert it even more, so many thing it can still do, awesome video Bud . 👍

[premo]

I love that you conduct impromptu experiments! That's what it's all about! I will absolutely give this a try in the future! Thanks!

[bjoernsk]

There's a bit about reusing spent blocks for Himematsutake on page 216, 3rd paragraph (3rd edition):

"Agaricus blazei can be grown on the recycled sawdust blocks from the end of the cultivation cycles of Shiitake (Lentinula edodes), Maitake (Grifoloa frondosa), Reishi (Ganoderma lucidum), and other primary saprophytes. Turning the compost piles made from the above for several weeks and mixing with wheat straw has provided a satisfactory compost medium for growing Himematsutake. The net nitrogen of composted Shiitake blocks approaches 2%, near the target nitrogen levels for classic Portobello composts. The use of this mushroom on “spent” substrates from the cultivation of primary saprophytes is on-going for idealizing a sequence of mushroom species growing on the same medium."

And I think the part you remember reading is on page 274, about 1/3 down the right side of the page:

"The “spent” blocks can now be recycled by pulverizing them back into a sawdust-like form. The expired Shiitake substrate is then resterilized for the sequential cultivation of Oyster, Maitake, Zhu Ling, or Reishi mushrooms. "

There's also a bit on the last part of page 337:

"Spent Shiitake or Oyster production blocks (sawdust/chips/bran) can be resterilized for further reduction by Stropharia rugosoannulata"

And then the main part of reusing spent blocks can be found in the beginning of chapter 22:

"At our farm, I have found that the spent substrate generated in the course of Shiitake cultivation is in itself a valuable by-product. More mushrooms can be grown upon it! The mushroom cultivator can implement a circuit of recycling by sequencing species on the same substrate, resulting in the maximum yield of mushrooms imaginable. Each decomposer produces its own unique set of enzymes that can only partially break down a wood-based substrate. Once the life cycle of one mushroom has been completed, the life cycle of another species can begin on the same substrate utilizing its own unique set of enzymes, taking advantage of the remaining undecomposed wood fiber and the dead mycelium of the predecessor mushroom. After this second decomposer exploits the remaining lignin-cellulose to its fullest ability, a third species can be introduced. And so on.… I have been able to grow four species in sequence with this method. After several generations of mushroom species, the mass of final substrate is a mere fraction of the original formula."

There's more on it in chapter 22, but I'm not going to copy the whole chapter here.

Great video as always.

[raduconstantin]

If you want to be less wasteful, put your SMB (spent mushroom blocks) to work for you. A SMB should be minced up and put in a new bag with fresh substrate by a ratio of 30 SMB to : 70 fresh substrate( whatever you usually use, wood pellets, straw, sawdust, etc). The Ideal CN ratio, the carbon to nitrate ratio for Pleurotus type fungi varies from species to species, but in general the ideal CN ratio for the fastest colonization times made in a study shows that CN 35 ~ 40 is best. To clarify CN 35 means for every 1 nitrate there are 35 carbon and to find out the CN ratio of your substrate there are numerous charts online that show the exact CN for different substances. Best of luck with your farm.

[hoodyk]

6:56 😂 I love your genuine confusion and pause at your own words, Lol, you needed to take a second to think about what you even said. Been really enjoying the content 👍👍

[Calvin]

Hey mate you have such a pleasant unselfish vibe. Thank you very much.

[AnthonyHandcock]

Interesting. I've only very recently come to mushroom cultivation and I'm really impressed with it as a hobby. The main thing I've learned so far is that if you can accept a few failures pretty much everything is either dirt cheap, free in the sense that it's lying around the house anyway, reusable or lasts indefinitely.

[rreinierr]

As a fellow (oyster) mushroom grower and clinical researcher I have to say I love these video experiments!

[pauloantunes]

OMG I never consider this possibility... More research is <3 Love your channel by the way

[KaptainKirk]

Great song choice at the end :) Thanks for the content!

[zumbapatty]

Was just reading Ch. 22 in Stamet's book and he does say that by reusing substrate, you risk additional contamination and recommends longer substrate sterilization.

[sayuas]

I am surprised you got such good harvests out of spent mushrooms, I wonder if it would be best to do it with different species since presumably different mushrooms use different nutrients from the block. For example first an oyster mushroom and then shiitake.

[rayyanali]

Improve mushroom cultivation (as in the channel) covered a research paper where they used spent substrate with different percentages. The bag with 50% spent and 50% fresh substrate produced pretty good result though 60% fresh with 20% used and 20% supplements was better.

[Yoggoth]

Chapter 22 is what you need, but also page 22 saying
"Species succession can be accomplished indoors. Here is one example. After Shiitake stops producing on logs or sawdust, the substrate can be broken apart, remoistened, resterilized, and reinoculated with another gourmet mushroom; in this case, I recommend Oyster mushrooms. Once the Oyster mushroom life cycle is completed, the substrate can be again sterilized, and inoculated with the next species. Shiitake, Oyster, King Stropharia, and finally Shaggy Manes can all be grown on the same substrate, increasingly reducing the substrate mass, without the addition of new materials. The majority of the substrate mass that does not evolve into gases, is regenerated into mushrooms. The con- version of substrate mass-to-mushroom mass is mind boggling. These concepts are further developed in Chapter 22."

[jacobjamar]

I really like your channel! I thought this was an old video. And I thought I'd already hit the bell... I was surprised that this came out yesterday. Was never notified, great video and keep up the great work!

[marialuciano]

You are producing a very beautiful mushrooms! Great job man!