Best Grain For Mushroom Spawn

Best Grain For Mushroom Spawn: A Top 5 Review

Grains are a great medium for mycelium. Once the mycelium hijacks the entire grain, it’s comparable to a mushroom seed. This is the safest and fastest way to grow mushrooms

So which is the best grain for mushroom spawn?

Among other factors, the best mushroom grain depends on the size of the kernel – the more surface area, the more mycelium can multiply. 

Today, we’ll look at some of the best grain spawns you can get directly from your local grocery store.

Let’s get started.

Different Types of Grains Spawn

Various spawn types, such as rye, popcorn, wheat, brown rice, and even wild bird seed, are used as mushroom grain spawn. Most of these grains are popularly and widely used in mushroom farming due to their water absorption properties and rich nutritional profile.

Rye Grain

Rye has an outstanding capability to retain water and doesn’t get mushy or burst when processed. Plus, A variety of mushrooms seems to enjoy rye spawn as a nutritional source.

Brown Rice

Brown rice is used mainly by industrial producers and appears to become a bit sticky/mushy when prepared. However, it may be a viable substitute for hobby growers.


Popcorn spawn is costly as compared to the other grains. However, it is very easy to find. You can most likely find them at your nearby supermarket.

The popcorn is a larger grain, which means that you would have slightly fewer inoculation points than other cereals.

Read more: The 5 Best Mushroom Popcorn Kernels in 2021

Wheat Grain

Wheat seeds are also an ideal alternative, and they are very similar to rye. The distinction is that wheat cannot retain the same amount of water, so they split more often when handled.

Organic wheat seeds can also be purchase in bulk grocery markets.


This is yet another excellent cereal grain. Inoculation points are provided in a large variety in millet. Since it is the smallest of the grains, it is typically combined to spawn with other grains.


Commercial producers also use sorghum. Sorghum is often used in livestock feed. However, non-human sorghum grain can be transformed into spawn cheaply by commercial growers.

5 of the Best Grain For Mushroom Spawn

It’s time to dive into the crux of it all. After all, we don’t want to keep you away from what you came here for! Here are our top 5 mushroom grain spawns.

1 – Liquid Fungi Sterilized Rye Berry Substrate Mushroom Grain Bags

These rye berry grain bags are great for beginner mushroom growers who have little to no expertise in mushroom cultivation. The rye berries used are sterilized and 100% organic. 

You get a total of 12 spawn bags, weighing 1 pound each. Gypsum and calcium play the perfect second fiddle to the rye berries in producing satisfactory results. 

Ideal for incubating mushroom mycelium, these sterilized rye berry substrate mushroom grain bags come in packages that are 12×12×6 inches in dimension. The thickness is both a feature and a necessity to maintain the block’s sterility.

You can use any three methods (e.g., multi-spore syringes, agar plates, liquid culture) to go about inoculation. A drawback is that it’s a tad expensive, especially if you plan to grow mushrooms on a commercial scale.

Product Specifications:

  • Manufactured by Liquid Fungi
  • 12×12×6 inches in size
  • 12 one-pound of rye grain berry bags


  • Ideal for incubating mushroom mycelium
  • Inoculation ready
  • Contains step-by-step instructions for inoculation
  • Additional nutrients for optimal growth
  • Organic and sterilized rye berries
  • Rye berries have the right moisture content
  • Thick bags for a sterile environment inside


  • Relatively expensive
  • Not ideal for commercial application

2 – Liquid Fungi Sterilized Rye Berry Substrate Unicorn Mushroom Grain Bags

A major difference between this and the previous product is the packaging. Here, the sterilized rye berries come in unicorn bags with injection ports, making inoculation a very easy.

The rye berry bags come in 2 bags of 3 pounds each, making it a total of 6 pounds. You get ideal amounts of grains at the price at which it comes. 

Besides this, a lot of features coincide. The rye berries are organic, sterilized, and are ready for inoculation. To assist the berries, there is gypsum (the previous one had calcium as well). 

You get step-by-step instructions on how to go about inoculation as well. Moreover, the unicorn bags are as thick as possible, which reassures sterility. You can use either multi-spore syringes or liquid culture to execute inoculation.

Despite the sterility measures, a lot of users have had their packages contaminated through no fault of their own. Residual condensation has also been noticed inside the bags on occasions. But maybe these were just one-offs. A majority of the reviews have been positive such as this one: “This is one of the best on the market. I put my syringe in each of these and BAM, Blue Oyster spawn…”

Product Specifications:

  • Manufactured by Liquid Fungi
  • 9×6×5 inches in size
  • 2 unicorn bags (3 pounds each) of rye grain berries


  • Inoculation ready
  • Inoculation instructions included
  • Sterilized and organic rye berries
  • Additional nutrients (gypsum) for optimal yields
  • Thick unicorn bags for sterility


  • Issues with contamination on grain
  • Excess moisture on occasions

3 – INTERGALACTIC MUSHROOM Sterilized Organic Rye Berry Vacuum Sealed Grain Bag

Handmade by experts, these sterilized and hydrated rye berries come packed in a 5-micron filter bag. The filter bag steers clear of any contaminants and facilitates fresh air exchange during incubation. Immediately after sterilization, this bag is put in a vacuum-sealed bag for foolproof protection and leaves no risk of contamination.

You get 2 bags of 1.5 pounds each with the least possible amount of burst berries. Moreover, the moisture level is optimum for perfect mycelium growth. 

The rubber injection ports make injecting your spores or liquid culture easy. The USA-grown rye berries are ready to use and come with detailed instructions. 

Pro tip: Use a dense spore syringe or a liquid culture that’s adequately germinated in a controlled environment to achieve colonization times of up to 2 weeks. Follow a grain/substrate ratio of approximately 20-30%.

Product Specifications:

  • Manufactured by Intergalactic Mushroom
  • 2 bags of 1.5 pounds each 
  • 7×7×5 inches in size


  • Sterilized and hydrated grain
  • 5-micron filter bag for fresh air exchange
  • Vacuum-sealed bag
  • Contamination free
  • Easy inoculation with rubber injection ports
  • Compatible with any mushroom strain
  • Made by experts in small batches for consistency
  • Full colonization in 2 weeks
  • Optimum mycelium growth
  • Detailed instructions


  • Some users received molded bags

4 – Generic Sterilized Rye Berry Self-healing Mushroom Grain Bag

A standout feature of the Generic Rye Berry Mushroom Bag is that they’re freshly made after an order is received. They do not stock packed bags in advance, which goes a long way in ensuring the sterility and freshness of the product.

The rye berries, just like the above products, are perfectly hydrated and sterilized. They are properly rinsed and soaked before bringing them to near boiling temperature and sterilizing them. 

Unlike the previous rye berry bags, you get one 3-pound bag of fresh rye berries with a self-healing injection port. The bag has a bowl-shaped with a handle at the top for easy carriage. 

It would’ve been better if the 3 pounds worth of rye berries came separated in two or three bags. This would prevent complete loss of berries in case of contamination or residual condensation.

Product Specifications:

  • Manufactured by Jomyco
  • 3-pound rye berry grain bag


  • Bags are freshly made upon order
  • Properly hydrated, sterilized, and nutritious grain
  • Rye berries can be inoculated straight out of the box
  • Self-healing injection port
  • Easy to carry and inoculate


  • Just one bag; more loss in case of contamination
  • No inoculation instructions

5 – Generic Sterilized Millet Mixture Self-healing Mushroom Grain Bag

This is probably the most unique from the grain mentioned above.  

Like the Jomyco rye berry grain bags above, this made upon receiving an order. The berries come from a local mill and are put in freshly made bags. It goes through the same processes: rinsing, soaking, heating to near boiling temperature, and sterilizing. 

As soon as you receive the 3-pound package, you can inject the mushroom spores with no waiting period involved. The self-healing injection port makes inoculation easier. 

The berries come all in one bag, which will all go to waste should slight contamination occur. Instead, separate bags would’ve been better for the same amount of grains.

Product Specifications:

  • Manufactured by Jomyco
  • 3-pound bag of milo/millet mixture


  • Bags are freshly made upon order
  • Self-healing injection port 
  • Hydrated and sterilized millet mixture
  • Can be inoculated straight out of the box


  • Just one bag; more loss in case of contamination
  • No inoculation instructions


Having discussed multiple options, now it’s time to zero in on the best grain for mushroom spawn and make your final decision.

We hope that this product review and buying guide has helped! For more mushroom-related products, books, and tips, visit us at