The simplified Guide to mushroom growth
There are countless methods to cultivating mushrooms, but there are some basic processes and steps that are generally consistent throughout the spectrum. Mushroom cultivation can be divided into four general phases:
Depending on the specie that you are cultivating or technique you are using, there will be variations to any one of these phases, but we will make sure to cover the basic concepts to get you on your way to becoming an expert cultivator.
This phase can often be considered one of the most critical processes to developing a successful cultivar since whatever occurs here will affect everything down the line.
All processes within this phase must be completed in an extremely sterile environment. This can be a clean room, a positive-pressure flow hood, or a still-air-box.
1. Developing a mushroom culture on an agar-filled petri dish
You will need either a healthy spore or tissue sample that will be placed on an agar petri dish, which is a nutrient rich media designed to maximize growth.
2. Developing a liquid culture from a mature agar culture (Optional)
This step involves the transfer of healthy mycelium into a nutrient rich mixture that is easily accessible using a syringe. Advanced cultivators will often develop liquid cultures because the risk of contamination is lower, compared to agar, and can reduce incubation time.
Note: There are several other methods to cloning or propagating a culture
In this phase, we introduce healthy mycelium from a culture to sterile grain, creating grain spawn. The grain will typically be stored within a glass jar or polypropylene bag. This process of combining mycelium with grain is referred to as inoculation.
1. Sterilization of grain
Before the grain can interact with the mycelium, all unwanted foreign bodies must be removed from the grain. This is done in a process called sterilization. A detailed How-To on sterilization can be found here [LINK].
Once the grain has been properly sterilized, you will introduce a sample of your mushroom culture to the sterile grain. Depending on how you have stored your grain and how you have prepared your culture will determine your inoculation process.
In this phase, the mycelium will grow exponentially by feeding on the grain. This process will often be the longest period in the cultivation cycle. More often than not, this can be between one to several weeks.
During this phase, any contaminants that were present at any point previously will become apparent. These can be present as colored molds or rotten smells.
If there are no contaminants present, you should see a thick layer of mycelium surround most of the grains. This means that we can transfer the spawn to a larger container and proceed to fruiting.
During the Fruiting Phase, your mycelium will begin to form fruiting bodies - the cap and stem structure that is commonly found with classic mushrooms. Here, we need to provide additional nutrients to the mycelium to give it that last push to create your harvest!
1. Fruiting Media/Substrate Preparation
Your fruiting media, also known as your substrate, will be a mixture of various nutrients that will induce pinning and fruiting. Typical substrates can include straw, wood chips, or compost.
Note: In many cases, your substrate should be sterilized in a similar process you sterilized your grains.
Once the substrate has been prepared, combine your substrate and spawn into a large, sterile container, such as a tote. Ensure the container is well ventilated with proper air filters and place in a clean, safe area.
Over the next few weeks, attempt to induce pinning by providing your mycelium with optimal environmental conditions. This can include misting, fanning, temperature changes, etc. You will eventually notice small bodies begin to protrude from the substrate - this is called pinning.
4. Fruiting and Harvest
Continue providing some tender, love, and care to your mycelium until your mushrooms mature into adult fruiting bodies. Harvest them when they are ready!
Just make sure to keep a few of the good ones to use for the Culture Phase so you can rinse and repeat