What is Grain Spawn?

 Disclaimer: What are Your Intentions For Growing or Using?

What Is Grain Spawn?

Please read this article: Basics About Fungi and Mushrooms

Reading this article will give you the basic understanding of mycelium, inoculation, germination, spores, and so much more.

Grain spawn is a little known secret weapon of the world of mushroom cultivation. Grain spawn is sterilized grain, that is spawning or growing the mycelium of the chosen mushroom type you want to grow. 

Once the grain has been sterilized, you introduce ONLY the chosen spores of the mushroom you want to grow. This introduction of mushroom spores to sterilized grain is called inoculation. This introduction can be from other grain spawn, spore syringes, liquid culture, or agar.

These spores will fully colonize or grow the mycelium throughout the container, eating and breaking down the food, or the grains, as the mycelium takes over. This allows for the mycelium to spread over each piece of grain. This makes it harder for other contaminants (other bacteria, mold, or fungi) to take hold in the grain because the mycelium you are growing is strong and extensive. 

You can grow any type of mushroom this way. 

It’s made from sterilized grains (like the rye berries that we are using), that have been inoculated with a live mycelium culture containing mushroom spores. These inoculated grains are consumed by the growing mass of mycelium. 

The fully colonized grain spawn can then be used as a start for a new culture, a start for a new jar of grain spawn, or it can be used in substrate (a special type of dirt that we will learn how to make later), in which the mushrooms can then grow their fruit body.

Why Use Grain Spawn?

Grain spawn contains a lot of energy or food for the mycelium to consume. It’s a bit like rocket fuel for mushrooms. Once it’s added to your substrate, it will grow like wild fire.

Eventually, the mycelium wants to start fruiting. To do that it will first create something called a hyphal knot. You can think of a hyphal knot as the beginning of a young mushroom, which is also knows as a primordium. These baby mushrooms or "pins" form a pinhead as it starts to evolve and sprout from it's mycelial phase. This phase is also called pinning. 

The picture below shows both pins and hyphal knots. The pins are colored brown, and look like the tiniest of baby mushrooms. The knots are white concentrated spots, that look like some thread has knotted up (what a great name for it... "knots").

When you read about others growing mushrooms, they will talk about "pins", and now you know what they are talking about. It's the smallest form of a fruiting body of the mushroom starting to grow. They look just like the top of a sewing pin.