Plans for mushroom composter

[Hippie3]

Mushroom Composter Plans
How to generate superior compost for mushroom growing on a small scale.
This method uses a styrofoam picnic cooler with a steam humidifier and a common light dimmer (or variable transformer) to control the steam and compost temperature. The final product is about 3 gallons of pure pasteurized compost in just 6 to 7 days. Total cost for the bits and pieces to construct this composter should be no more than $30.
MATERIALS NEEDED TO CONSTRUCT COMPOSTER
Styrofoam cooler
Steam humidifier or vaporizer (VICKS Warm Mist or similar)
Bottle, one gallon or larger
Hose (2 feet) that will fit mouth/cap of the bottle
Wooden sticks (5), each being 2 feet in length
Single pole, solid-state dimmer switch
Metal mesh screen (4 sqaure feet with a 1/4" or 1/8" mesh size)
Long stem thermometer, 120ƒ C, scientific or kitchen (meat therm.)
The construction of the composter utilizes a styrofoam cooler, preferably one close to 14 inches by 22 inches by 15 inches deep in size. Six 3/4" holes, evenly spaced across the surface of the lid, are melted with a soldering iron or cut with a knife. Six more holes of the same size are melted or cut into the body of the cooler, three along each side, two inches up from the bottom edge. On the short sides of the cooler body, one hole is cut or melted on each side at the bottom edge. One of these holes is sized 1/2", and will serve for drainage. The other end has a hole cut just the right size to accommodate the steam output head or nozzle of the steam humidifier.

The bottom of the cooler is lined with aluminum foil, being careful to not obstruct the drain or steam inlet. A screen support is made from the 1/4" or 1/8"-mesh screen (sometimes called hardware cloth). The screen is cut 8 inches larger than the dimensions of the bottom of the cooler. 4 inches of screen are folded 90ƒ at each edge to form supports, which hold the surface of the screen 4 inches above the bottom. The compost sits on the top surface of the screen so that the steam can flow evenly underneath the compost. This screen support should fit the bottom of the cooler without large gaps around the edges.
A single-pole solid-state dimmer is used to control the humidifier power. Good wiring and insulating procedures need to be followed. If you aren't knowledgeable about wiring, find someone who can help. It is important for safety that the wiring be correctly installed. The best method is to wire the dimmer switch (in a plastic electrical switch box) to both the power-cord of the humidifier (cut off the plug end[male]). Then take an extension cord (cut off the plug end[female]) and wire it to the dimmer switch.
Things to check for:
1. The maximum capacity of the dimmer switch (in Watts) should be greater than the load imposed by the humidifier. (almost all dimmers have the necessary rating)
2. The wiring methods should be well insulated and suitable for the damp environment it will be used in.
Finally, a water reservoir is constructed. Arrangements are made to secure a one-gallon or larger water bottle above the humidifier. A 1 and 1/2-inch hole is cut in the top surface of the humidifier body to accommodate the hose. The humidifier is filled with water to the "fill" line, and the hose is inserted so that the open end of the hose hangs 1/2-inch below the fill line. In this way a constant level of water is maintained in the humidifier, which makes the steam output constant for a given dimmer setting. It is important to maintain accurate steam / temperature settings during a composting run. During a run, the humidifier electrodes must be cleaned at least every other day, or output will be seriously effected. Using distilled water is a slightly expensive option to regular cleaning.
Before the first time a composter is used, it is best to set it up where in the final location, tape all the holes closed except the drain hole and the humidifier nozzle hole on the bottom, fill up the humidifier and reservoir jug with water and turn on the humidifier at full power dimmer setting allowing the cooler to steam for 4 hours or so to eliminate any plastic or chemical odors and to test your composter's operation.
To begin a compost run:

Mix in a bucket, approximately 2 and 1/2-gallons of shredded straw with 1 gallon shredded dry fresh manure (cow or horse). Mix in 3 to 4 ounces cottonseed meal or 1 to 2 ounces blood meal (nitrogen sources, available at most plant nurseries). Add 3 and 1/2-quarts of hot water, preferably with a sprayer, and mix thoroughly. This warm mixture is loaded into the cooler without delay, loosely filling the cooler to within 1 to 2 inches of the top. Five sticks are placed in the cooler before adding the compost mixture, so that after the compost is loaded, 2-inch square ventilation shafts can be created by wiggling each of the sticks around. The sticks are withdrawn, and the lid put in place, all the vent holes are taped shut except the one on the lid furthest from the steam nozzle, and the dimmer set on maximum. The thermometer is placed through the untaped hole so that it is measuring the middle of the compost.

During the first phase of the run pasteurization occurs, killing all insect life. Note that this is opposite of how it is done at a commercial mushroom farm or in outdoor nature composting, where pasteurization is done at the end of a composting run. After about 2 hours of full power steaming, the temperature should rise to approximately 65ƒ C (60ƒ to 70ƒ). Quoted temperatures are only a rough guide, try to maintain the temperatures within the given ranges. For this first phase it is necessary to reach a minimum of 60ƒ C. Once the temperature reaches 60ƒ C check the time and let the compost remain above 60ƒ C. for 3 to 4 hours.
At the end of this time remove all the tape from the ventilation holes and leave the dimmer setting on full. Within a day ammonia will be noticeable in the exhaust steam and the temperature should be 55 to 65ƒ C. Hold this temperature for 2 to 3 days. After the first day the ammonia odor should disappear. After this happens, white fire fang, or actinomycete fungi, will be apparent in the compost. It is best to allow the compost run to proceed undisturbed, but if you wish to check it is okay to briefly lift the lid and move the compost surface. Don't allow the compost to cool during any brief investigations. At the end of the 3 days actinomycete should be prominent and there should be no ammonia smell. If not, extend the high temperature phase for up to an additional day.
The dimmer setting is now lowered slowly so that the compost temperature drops 2ƒ to 3ƒ every 2 to 3 hours, until a temperature around 50ƒC is reached (45ƒ to 55ƒ). The compost is then held at this lower temperature for 3 to 4 days. At the end of this time the power is turned off and the compost is allowed to cool slowly inside the closed cooler. It is ready to lay out and spawn when the temperature cools to 24ƒ to 28ƒC. It is best to spawn the compost immediately after it has cooled, although it can be stored for a few weeks if necessary.
The compost made in this way is usually excellent, comparable to the best commercial mushroom farm compost. An added benefit is that new compost recipes can be experimented with in small quantities and in short time frames. One extra is that the drain water makes an exceptional organic fertilizer for houseplants.
Notes:
1. The formula for compost here is very basic. With trial and error many materials can be formulated into usable compost. In particular, it is important to mix for the correct carbon / nitrogen ratio (saccharides / protein). Any properly balanced mixture suitable for large scale composting is suitable for use in this composter. Very useful tables of compost ingredients are included in The Mushroom Cultivator and Growing Gourmet and Medicinal Mushrooms, both by Paul Stamets.
2. Some species of mushrooms culture well on ordinary pasteurized straw with no additions. This composter is ideal to pasteurize straw. It is much simpler and more accurate than immersion in hot water or other methods. Just load with shredded dried straw and pasteurize at greater than 60ƒ for 4 to 6 hours. Allow to cool slowly covered, and spawn when the temperature is less than 28ƒC. Typically the straw will be at proper moisture content when unloaded.

[GoVols]

So today I went to the stables behind my parents house and got about 70 pounds of hpoo in a big container. The guys said that that particular pile was old, so I dont need to leach it out.

But there are hundreds of bugs crawling around in it. Do I need to get rid of these some how, and how if I do? Or do I just need to kill them, assuming the pasturization process will do that for me and leave the dead critters there?

[reverend trips]

I would spread it out on a tarp outside and let the sun dry it out for a few days.

[Freaky]

I agree with Rev.

Taking the amount you need, spread it out, let the sun bake it dry. This should drive the bugs out. Then pasteurize for use.

[GoVols]

Im going to need to use it this comming weekend (this is Sunday night, so Ive got almost a whole week) but it is supposed to rain most of the week, will this effect it? Should I wait till its going to be sunny for a few days?

[Lazlo]

If the manure's weathered or composted down properly and ready for use, i'd go ahead and pasteurize it. That will kill off the bugs and the bacteria or mushroom mycelium will eat them shortly there after. Bugs in composts are a common problem that most mushroom farms have to deal with.

[bugs]

Keep in mind that this is just another crackpot idea from someone who hasn't done it, but I think I'd do the tarp thing with what I needed for the next few weeks, and compost the rest. The heat of composting would kill the critters -I think that's enough to generate some good heat if somewhat contained- and the compost is supposed to be really good for the fungi.

Just a thought....

[GoVols]

I spread out two trash bags and coverd them up with poo. Got about 50lbs left in the tote. I would immagine that is enough to start composting it.

I have never done that before though. Do I just let it sit there and it will compost on its own, or do I have to add some stuff?

[bugs]

50 pounds should be fine. You'll want it in some kind of a bin to keep in the heat and moisture, with lots of holes for air circulationb.. A few boards and some chicken wire works well. heaping it up in a pile and covering it with a cheap tarp works too.Try googling 'compost' or 'making compost' and surf for a while, there's a lot of good info. Also, Paul Stamets' book on mushroom cultivation has a lot of mushroom-specific information and it's a great reference for our hobby. And, of course, check the archives here!

Remember, I'm speaking from limited experience and that from making compost for the garden. I'll be researching mushroom compost more as time goes on, but I'm pretty much a beginner myself. So much to learn, so little time! Good luck, my friend.

[GoVols]

Thanks man.

If the more is better, the pile I got mine from probibly weighed 2 tons. So I can get as much as I want. Ill look into it.

Never knew I would appreciate the stables right down the road from the house not 3 miles.

You Rock

[Lazlo]

If you look toward the core of that pile you got the manure from, you'll see a composted manure that's now a rich soil. That's prime time stuff. Simply pasteurize the soil for 2 hours @ 150 degrees and spawn.

[Hippie3]

check now the new first post in this thread...

[bugs]

Thanks, Hip. That's a nice setup. I was hoping that someone would come along and put some practicality to my guesswork. Especially the stuff to add to the poo, that's valuable info.

Some cow flaps are due to land in my backyard soon, and if they do I'll be using a little different technique - bigger pile, self-heating. I'm trying o get hold of a 50 gallon plastic barrel to make into a composter. If the cows do indeed flap, and it all works, I'll do a write-up.

[GoVols]

Originally Posted by Lazlo

If you look toward the core of that pile you got the manure from, you'll see a composted manure that's now a rich soil. That's prime time stuff. Simply pasteurize the soil for 2 hours @ 150 degrees and spawn.

Thats where I got mine because thats what the fat man on the stool in the barn told me to dig up. He said it was better.

Today is the big day though, time for pasturization, yall wish me luck, I got 2 qts of corn/myc whose future depend on my proper pasturization.

Hip, awsome set up, when. Would love to try that some time.

[Hippie3]

i'm sold on steam, perfect every time

[GoVols]

How do you steam yours hip?

I would immagine a large pot and a bag of somekind situated above the boiling water for a few hours.

Oven bag in the oven has been working alright. But the flushes are inconsistant. I use mainly the cheap alluminum pans that are like 12X4x4 (meat loaf size) and the flushes are usually around 200 grams, harvested two yesturday. One was a first flush of creeper that weighed in at 357.5 (my personal best so far), the other was a second flush of MexiPal that was just under 90, the furst flush on that one was 180.

With multispore I can not be sure, but I think the inconsistant flushes is due to the fact that I do not have the hydratrating of the poo down to a science. Just kina add till it looks right. Lazyness, I know.

[Hippie3]

yep,
i get cheap old pillowcases at the thrift store
load in the poo
place them on a stand-off above the water line
then gently steam it a few hours
until core temp reaches about 160*F
then i shut off the heat and let it cool.