Four Stages Of Mushroom Cultivation
This article provides a high-level overview of the phases of growing mushrooms. If you are looking for a more detailed walk-through with pictures and instructions, please see our post on How To Grow Mushrooms At Home.
Genetic Culture Phase
A friend of mine once told me, the five rules to massively successful mushroom grows are
- Environmental Conditions
Overlooked by some, starting out with quality genetics is crucial in determining the quality and quantity of the fruits your grow will produce and plays a roll in every step of the cultivation process.
Generally speaking the three most common types of cultures used are multi-spore, liquid culture and agar culture.
Multi spore cultures consist of the collection of spores on foil or other medium. These spores can then be added to agar, put in a syringe with sterile liquid.
Multi Spore is a literal gumbo of genetics. That said, the fruiting bodies produced when using spores will be diverse as related to isolation’s using agar or liquid culture.
Agar cultures are living mycelium growing on a nutrient rich gelatinous material. These living cultures can grow from dropping spores on an agar plate, by taking a culture from a live mushroom fruit, or by transferring mycelium via a variety of other methods. The agar culture may then be used to incubate grain spawn, further isolation of genetics, used to make liquid culture, or stored as agar slants.
Like Agar Culture, liquid culture is living mycelium suspended in a nutrient rich broth. Liquid culture is made by dropping an agar culture in to a sterile broth. The broth allows the mycelium to grow and multiply, as well as provides an environment allowing the mycelium to survive longer than an agar culture.
During this phase the genetic culture will be introduced to a spawning substrate which will begin the growth cycle. The mycelium will begin to consume the high nutrient substrate, completely covering the material with delightful white mycelium.
This phase will be broken down it to two parts.
1) Choosing ideal spawn substrate
2) Introduction of culture to spawn
A spawning substrate is a nutrient rich material that the mycelium will consume. When choosing a spawning substrate you will need to research the ideal spawn material for fungi species you are cultivating. Common spawn materials are grains, seeds, and hardwoods. The spawning substrate is crucial in healthy mycelium development and must be prepared in advance to suit the mycelium’s ideal conditions. Preparation will include hydrating the material, packing in to a spawn vessel, and sterilization. Sterilization is necessary to kill any other organisms that may compete with the fungi culture to consume the delicious grain spawn.
During this phase you will be introducing your genetic culture to a sterile spawn medium. This medium is referred to as a spawning substrate and will vary based on the mushroom you are attempting to grow.
You may introduce your genetic culture a variety of ways, however the most common are, injection using a spore syringe, injection using a liquid culture syringe, or by dropping a piece of agar culture in the spawn substrate.
During this phase the mycelium will begin to develop, grow and multiply, extending its reach throughout the spawn substrate. Again, this phase will be broken down in to two parts.
During this phase mycelium will begin to form and slowly colonize the spawn material, consuming the high nutrient substrate.
Within the process of digestion, mycelium will consume the nutrition from the substrate and emit carbon dioxide
Because of this, it is important that you’re growing vessel includes a filter that allows for gas exchange, which is eliminates carbon dioxide buildup and replaces excess CO2 with fresh air.
Depending on the species, the spawn substrate type, and conditions, full colonization can take anywhere from 2 to 6 weeks.
During this phase you will begin to monitor environmental conditions. Growing mycelium should be kept in an ideal temperature range. For example, P. cubensis colonizes most rapidly between 75-80°F (24-27°C).
Spawning to Bulk
A common method of growing mushrooms involves mixing the colonized spawn material with a non-nutritious, hydrated bulk substrate. This not only allows you to get more out of your spawn material, but also provides additional hydration which is essential for subsequent flushes.
Common bulk substrates include things like coco coir, manure, vermiculite, straw, and other organic materials.
The next step in the process is to introduce the colonized substrate to conditions that will promote fruiting of the mushroom body.
To promote fruiting you will introduce your fully colonized substrate to higher air exchange while maintaining a high humidity (<90%) in the chamber.