How to Know What Seed to Grain to Substrate Ratio to Use?

Before embarking on the journey of growing mushrooms at home, there are several factors. One of them is the ratio of seed, grain and substrate.

In this article, we will focus on the seed/grain/substrate ratio and its importance in mushroom cultivation.

What is Seed to Grain to Substrate Ratio?

The seed to grain to substrate ratio is the ratio of fungal spores, seed to grain, and substrate used in the cultivation process.

The proportion varies according to:

• The type of mushroom you are growing
• The grain seed you are using
• The substrate in which you are growing your mushrooms.

Why is Seed to Grain to Substrate Ratio Important?

Colonization

Firstly, it affects the colonization time, which is the period during which the spores of the fungus colonize the substrate.

The correct ratio can help reduce colonization time, which can speed up the cultivation process.

Quality

Second, the ratio can influence the yield and quality of the mushrooms. The correct ratio can help produce more substantial, healthy, and robust mushrooms.

Crop Success

Finally, the ratio can also affect the overall success of the cultivation process. An incorrect ratio can cause contamination, slow growth or even crop failure.

Types of Mushrooms and Their Seed to Grain to Substrate Ratio

There are several types of mushrooms that you can grow at home, each with its unique seed to grain to substrate ratio. Here are the ideal ratios for common types of mushrooms:

Portobello Mushroom 

• Seed: Approximately 1 to 2% of the total substrate volume
• Grain: Approximately 20 to 30% of the total substrate volume
• Substrate: Approximately 70 to 79% of the total substrate volume

So, for example, if you are using a 5-gallon bucket to prepare your substrate, you might use around 1/2 cup of mushroom spores (seed), 1-1.5 gallons of grain, and 3.5-4.5 gallons of substrate.

Crimini Mushroom

• Seed: Approximately 0.5 to 1% of the total substrate volume
• Grain: Approximately 10 to 20% of the total substrate volume
• Substrate: Approximately 80 to 89% of the total substrate volume

So, for example, if you are using a 5-gallon bucket to prepare your substrate, you might use around 1/4 cup of mushroom spores (seed), 0.5-1 gallon of grain, and 4-4.5 gallons of substrate.

Oyster Mushrooms

Oyster mushrooms are one of the easiest mushrooms to grow at home.

The ideal seed to grain to substrate ratio for oyster mushrooms is 1:5:20.

This means that for every 1 part of mushroom spores, you should use 5 parts of grain spawn and 20 parts of substrate.

Lion’s Mane Mushroom

• Seed: Approximately 1 to 2% of the total substrate volume
• Grain: Approximately 20 to 30% of the total substrate volume
• Substrate: Approximately 70 to 79% of the total substrate volume

So, for example, if you are using a 5-gallon bucket to prepare your substrate, you might use around 1/2 cup of mushroom spores (seed), 1-1.5 gallons of grain, and 3.5-4.5 gallons of substrate.

Shiitake Mushrooms

Shiitake mushrooms are a bit more challenging to grow than oyster mushrooms, but they are still suitable for beginners.

The ideal seed to grain to substrate ratio for shiitake mushrooms is 1:5:50.

This means that for every 1 part of mushroom spores, you should use 5 parts of grain spawn and 50 parts of substrate.

Button Mushrooms

The ideal seed to grain to substrate ratio for button mushrooms is 1:3:10.

This means that for every 1 part of mushroom spores, you should use 3 parts of grain spawn and 10 parts of substrate.

How to Calculate Seed to Grain to Substrate Ratio

Calculating the seed to grain to substrate ratio is relatively simple.

You need to determine the weight of each component and then divide it by the ratio.

For example, if you want to grow oyster mushrooms and need 10 pounds of substrate, the calculation would be as follows:

1:5:20 ratio

1 part mushroom spores = 10 / 20 = 0.5 pounds 5 parts grain spawn = 0.5 x 5 = 2.5 pounds 20 parts substrate = 0.5 x 20 = 10 pounds

In this example, you would need 0.5 pounds of mushroom spores, 2.5 pounds ofgrain spawn, and 10 pounds of substrate to achieve a 1:5:20 seed to grain to substrate ratio.

To calculate the ratio for other amounts of substrate, you can use the same formula but adjust the weight of each component accordingly.

For instance, if you want to use 20 pounds of substrate, the calculation would be:

1 part mushroom spores = 20 / 20 = 1 pound 5 parts grain spawn = 1 x 5 = 5 pounds 20 parts substrate = 1 x 20 = 20 pounds

Therefore, you would need 1 pound of mushroom spores, 5 pounds of grain spawn, and 20 pounds of substrate to achieve the same 1:5:20 ratio for 20 pounds of substrate.