I am starting a monotub and have a hard time finding dried horse poo that is not processed (compressed into pellets).

There is virtually no company selling plain dried horse manure in my country, only the compressed pellets that should be mixed with water.

I am afraid these pellets will turn into mud or strong watery soup and I won't know how strong it is since all the bulk subtrate recipes use plain manure, not pellets. This may render the substrate unusable. I may also have to add a lot of straw, coir, verm, peat and other stuff only to make it hold water, driving the cost up.

Do you have any experience with these pellets? One vendor says it has extra straw in it and sells it as tablets/pucks but still...

If you're new to growing I would highly recommend you use coir.. You don't have to pasteurise.... just pour boiling water on it in an esky and leave it 45 minutes... squeeze out by hand to field capacity as you put it straight into your mono.

You've got a garden shop in your country hey mate?

Seeing as manure typically needs leaching in the rain, the rehydration process should give you some kind of solids which you can strain out, if only with a t-shirt or pillowcase. Try a small amount first?

That said, I can get all the straw-free horse dung I want, free to collect. Hmmm....

Yes but I need nutritious subtrate and stick with the "official" recipe, hence the need for manure. I did several batches of PF tek already yields are low so I need to scale up.

I've got all the ingredients and tools so far except for the horse poo. I never expected a simple poo would be so hard to obtain.



I found straw can be mixed with the pellets in 1:10 ratio but this shifts the problem of getting manure to a problem of getting straw. No garden shop I found has it.

People don't usually buy this stuff and the want pellets for their garden flowers, not for making substrates so the shops simply don't have this stuff on the shelves.

The same thing with straw. One can get tons of straw from agricultural vendor but you won't find any in a garden shop. I found some straw in a pet shop but this might be overpriced.

1 kilo of straw for about 1.20 USD and guess what - it comes in PELLETS!

The non-dried manure I use is "Black Kow" and contains 30% moisture, so maybe start by trying to add 3/7 of the pellet mass as water (30g of water for every 70g of pellets)? Maybe start with small samples/tests until you are happy. Or in the example above you can add 15g of water and slowly add more?

Good luck! I wish you a bountiful forest of mushrooms

Thanks. Black Kow is not available in my country (one part of Europe) but I think the best bet would be to get pellets with extra straw and some additional straw, then mix it and experiment.

Unfortunately the vendor does not specify the "compression ratio" or how much pellets are equivalent to the original unit of poo.
This may lead to overshoot the nutrition content and this will be a disaster (from sporadic growth to contamination outbreak).

I will also ask some mushroom growing suppliers in the area. They may know...

If you can’t get any manure coco coir and vermiculite work just fine for a bulk substrate. In another dimension I’ve seen some pretty good results from following damion5050s coir tek and adding in a half cup of gypsum

I found two recipes for the dehydrated horse manure:

10% dehydrated manure, 40% straw, 50% coco coir
10% dehydrated manure, 40% vermiculite, and 50% straw

Several different sources agree the pelletized manure is about 10x stronger than normal sundried horse poo.

So I will just get some straw from a pet shop, mix and pasteurize.

It seems it's not a big science, the manure is there just to add essential nutrients so as long as the substrate holds water well and is properly pasteurized it should work well (I hope).

^ agreed. There are as many substrate recipes as there are growers. The key is to have the right moisture (field capacity) and pasteurize properly. Good luck sounds like you are on the right track!

Thanks. I will post the results, first testing it on a mini-monotub, then going full scale.

The pressure cooker will arrive tommorow so this will be a quite exciting weekend

Congrats on the PC!

I forgot to mention the air circulation design of the monotub (where supposedly heavy CO2 leaks from the bottom row holes and is replaced by fresh air from the top holes), that is also very important. Too little automatic air exchange and the mycelium could choke. Some claim slow leaking CO2 by making the bottom holes smaller and tightly packed with polyfill can cause some small amount of beneficial CO2 buildup and promote fruiting and that there is an optimum monotub design.

So it is 3 key things I would put at the top: moisture/pasteurization/CO2%.

PS: I've had two monotubs fail. Once thinking that air exchange through the list would be enough (probably choked the mycelium in a pool of CO2), and another time due to too much moisture (failed the squeeze field capacity test with a little trickle but decided to give it a try anyways).

Thanks blue.magic for looking into the data. This is rather useful - best wishes for your grow!

Okay so I have used the following recipe from MycoSupply:

10% dehydrated manure, 40% vermiculite, and 50% straw

This is by weight and translated to following amounts for 1 pint grain jar:

25 g dehydrated manure
80 g vermiculite
100 g straw

I have mixed all ingredients and the total volume was about 2 200 ml, therefore I added 110 ml gypsum (5% by vol.).

I have used the pillow method, i.e. mixed everything in a pillowcase and pasteurized inside the pillow, then strained in collander.

Unfortunately, the substrate is very airy and bulky, it's almost all straw and no manure. The pellets kind of dissolved into the water with few bits of poo left at the bottom of the pillow case.

The substrate looks like spaghetti where the vermiculite is like parmesan sticked on the pasta with occassional meat balls of poo. It's nowhere near compact soil-like substrate

Anyway, I have loaded two mini monotubs with three layers of this mix and two layers of colonized grain. I don't think this will work but let's see.

Next time I will try the method shown in "Let's Grow Mushrooms", i.e. mix everything with water until reaching field capacity and then load into jars and pasteurize within jars. This way all the nutrients stay in the substrate.

Unfortunately, the straw is kind of airy and bulky and very different from the straw pre-digested by the horse.

I took image of the pellets - they expand into something resembling poo (diarrhea kind of poo) but adding water just to expand it will already throw out my ratios.

Maybe it would be possible to grind the straw somehow before mixing with hpoo to make the substrate less airy. Or I will try coir or maybe just vermiculite instead. I guess one cannot have too much poo, only too little, right?

I know it's best to have real dried horse shit, but every garden shop sell just these pellets and the pet shops have just hay (only ONE had straw). Now I have few kilos of these pellets and straw. I hope I will make use of it somehow...

Hmmm... it seems it would be easier to just grow the mushrooms on straw and "enhance" it with hpoo pellets and gypsum. I should have also cut and maybe soak the straw beforehand.

What about coir?

The only (inexpensive) coir I can find comes in compressed bricks and I don't know how much it will expand after adding water. Even then I don't know how much % grain spawn to add (and % by weight or by volume...)

I have to experiment with it more - I hope I won't run out of substrate before finding some mix that actually works
Unfortunately the recipes around are for common items and specific brands in US that I cannot find equivalents for in Europe, I don't even know what to look for...

I think the recipe from MycoSupply is only for spawn bags and pre-cut straw (they have not mentioned it) and probably not even for cubensis.

You should be able to substitute chicken manure pellets for horse manure. This is the guide I followed successfully to grow Panaeolus cyanescens...the grower started off using horse manure in the substrate but later switched to chicken manure pellets for convenience.

http://www.en.psilosophy...f_copelandia_cyanescens_(psilosophy.info).pdf

His substrate recipe:

Mhm, coir and verm I use [for the exact reason/method you stated above Northerner], also with a bit of gypsum and spent coffee grounds. Nice, meaty fruits and plenty of them.

Also I'd think if you have local farms near you you could possibly talk with some of the farmers and ask about collecting some of their poo [after it's dried out and has lost a bit of its smell].

Thanks.

I have horse manure pellets (several kilos of it) so I will try different substrate recipes until I arrive to something more compact that can be made into a monotub/growbox.

I also have several spawn bags so one alternative is to make straw logs, possibly enhancing the straw with dissolved horse manure pellets during the pasteurization.