grain spawn Archives - Spawn Magic

We were inspired to dedicate this article exclusively to mushroom spawn bags, as some of the terms used in mushroom cultivation might appear daunting to novice cultivators. But what exactly are these bags? What lies within their confines? Fasten your seatbelts and get ready for a comprehensive journey through the necessary mushroom-growing components.

What Is a Mushroom Spawn Bag?

Establishing the concept of a spawn bag marks a robust initial stride in comprehending the essential elements of mushroom spawn bags. Referred to alternatively as mushroom grow bags, these items play a crucial role in cultivating substantial quantities of mushrooms within a confined space.

Constructed from sterile plastic materials, these bags are usually equipped with a filter port to facilitate the exchange of pristine air with the mycelium. Certain variants of these growth bags even arrive pre-packed with the untainted growing substrate. Best spawn bags should possess both breathability and the ability to ease a culture injection via the inoculation port.

Check our article on How To Make Sterilized Grain on your own!

What Are the Features of a Mushroom Spawn Bag?

Spawn bags feature a gusseted design, characterized by inward-folding sides. Additionally, these bags are autoclavable, designed to withstand the high pressure and temperatures within an autoclave or sterilizer. This heat resistance is vital as growers introduce spawn bags into pressure cookers. To prevent any issues with melting, the majority of spawn bags are crafted from polypropylene material.

Moreover, spawn bags serve as effective vessels for containing grains during the sterilization process. Positioned at the forefront of the bag is a filter patch, ensuring a steady inflow of fresh air for the culture while effectively warding off contaminants.

What Can Mushroom Spawn Bags Be Used For?

Spawn bags can be used for multiple different things. They can serve as a valuable tool for generating ample quantities of primary-generation grain spawn within preliminary test batches. These bags can also be used as a fruiting chamber, creating a humid dome good for the mushrooms fruiting phase. That’s not all, they can also be recycled and reused!

Spawn

When creating an initial generation of grain spawn many people opt for mason jars which is okay. However, grain spawns will find greater efficiency when used in grow bags. Opting for a grow bag as your spawn vessel offers the advantage of effortless breaking and mixing of the spawn. This will accelerate the colonization process. Additionally, using grow bags for your spawn can also simplify the task of evenly distributing your spawn onto a bulk substrate.

Read our article How To Make Mushroom Grain Spawn on your own!

Fruiting

Don’t forget that these bags are also referred to as the “grow bags,” thus it’s not surprising that they can be used for fruiting your mushrooms. The bag’s upper portion creates a humid shelter, encouraging mushroom fruiting. It’s important to bear in mind that the interior of the bag might not receive a substantial quantity of fresh air.

Hence, if you choose to employ the bag for mushroom fruiting, it’s important to regularly open the bag’s top to ensure proper fresh air exchange. However, exercise caution and refrain from opening the bag until the block within is fully colonized, as premature opening could lead to contamination.

Repurposing

Truth be told, the best practice is to start your mushroom-growing journey with new spawn bags. However, they can be repurposed for other tasks if they have not been cut open for the fruiting phase. They can be used for pasteurizing casing layers or even the substrate.

While spawn bags can be repurposed, keep in mind that their structure will degrade over time and the filter patch will also become ineffective after multiple sterilization cycles. That’s why the best idea is to start with fresh, brand-new bags.

Mushroom Spawn Bag Specifications

When choosing a mushroom spawn bag, there are a couple of things to keep an eye on, and here’s what:

Filter

Generally, the filter is designated with a micron rating, indicating the pore size of the filter itself. These ratings typically range from 0.2 microns to 5 microns. For applications involving fruiting blocks or spawn bags, it’s advisable to opt for a lower micron rating, preferably not exceeding 0.5 microns.

Material

Spawn bags are available in a spectrum of material thicknesses, typically ranging from 2.2 mil to 4.0 mil. Bags of 2.2 mil thickness serve equally well, there is a slightly higher chance of tearing during regular handling but it’s negligible.

Dimensions

Mushroom spawn bags come in various sizes usually 1.5lbs and 3lbs, if they are pre-made. When choosing a ideal bag size you need to take into account things like the dimensions of your sterilization equipment as well as the grow room.

How To Use Mushroom Spawn Bags

When working with spawn bags always be in a sterile and clean environment wearing latex gloves and a breathing mask. You don’t want to mess up your substrate or the mycelium by introducing them to contaminants. Use rubbing alcohol to clean your gloves and equipment working under the laminar flow hood or in a still air box.

Start by unsealing your spawn bags and filling them with the substrate of your choice.
Place the loaded bags in a pressure cooker or a sterilizer and begin sterilizing them.
Allow the bags to naturally cool down to room temperature.
Make sure that the bags are sealed properly upon removing them from your pressure cooker or sterilizer.
The next step is to inoculate your bags.
Using a syringe inject the culture through the self-healing injection port, making sure that the needle is flame sterilized after each use.
Place the grow bag in a warm location with indirect lighting.
Regularly monitor the bag to prevent the substrate from drying out. If it does become dry, inject filtered water using a syringe.
Wait for the bag to get fully colonized.

In the realm of mushroom cultivation, grain spawn goes beyond being a mere puzzle piece within the mycelium assembly – it serves as the entire toolkit, if not the workshop itself! It’s the unsung hero working behind the scenes in our mushroom stories, quietly preparing the stage for the spectacular flourishing of fungi that we all adore. Creating grain spawn is a phase of mushroom cultivation that can involve the entire family and is something you must learn if you want to improve your mushroom-growing skills. The procedure for crafting grain spawn remains nearly identical, regardless of the specific mushroom variety you’re aiming to grow.

The primary purpose of grain spawn is to create a controlled environment where your selected mycelium can thrive and proliferate. This growth happens before you allow it to spread within your fruiting (bulk) substrate. For this endeavor, your grain must be completely sterile. The most convenient method for achieving sterility as a home cultivator involves utilizing a high-quality pressure cooker. Let’s start from the beginning and dive headfirst into the world of grain spawn!

What is Grain Spawn Exactly?

Grain spawn stands as a widely adopted medium for cultivating mushrooms. It is created by sterilizing grains like rye, wheat, or millet, followed by the introduction of mushroom spores or mycelium. Over time, the mycelium proliferates and encompasses the grains, forming a network of fungal cells that can subsequently be utilized to inoculate larger substrates such as sawdust, straw, or wood chips.

This method of using grain spawn has gained popularity in mushroom cultivation due to its comparative ease and cost-effectiveness in contrast to alternative techniques. The grains offer a nourishing foundation for mycelium growth and maturation, with the sterilization process acting as a safeguard against contamination from other microorganisms. Grain spawn proves versatile in nurturing a variety of mushroom species.

How To Make Mushroom Grain Spawn

Grain spawn is the cherished offspring of your mushroom venture, acting as a vital middleman between you and the fungi. This process involves the fusion of sterilized grains with mycelium, the vegetative component of a fungus. Together, they forge a captivating symbiotic relationship, with the mycelium embracing the grains, orchestrating colonization through its intricate network of thread-like cells.

Making Mushroom Grain Spawn In Jars

Let’s break down the process into 5 easy to follow steps that will teach you how to make mushroom grain spawn on your own:

Preparation

The grain will act as the prime nutritional resource for your mycelium. Therefore, handpick it and check if everything is alright.

Soak the Grain

Thoroughly cleanse and soak the grains. To soak the grains, simply place them in a bucket or bowl, cover them with water, and allow them to sit for a span of 12 to 24 hours. Be mindful not to exceed the 24-hour mark, as extended soaking might lead to sprouting. Depending on the type of grain utilized, its volume should increase by approximately 2 to 3 times.

Modify the Jar Lids

You’ll need:

12 glass mason jars of approximately 500ml (1/2 quart)
Metal lids for the jars
A screwdriver or a large nail, a hammer, and a wooden block
A small quantity of polyfill

These unique lids are designed to enable you to inoculate the sterilized grain without the need for a laminar flow hood. Simply drill two holes on the lid’s top surface, a bigger one in the center while the other smaller one should be closer to the edge. Once the smaller hole is drilled, apply a small amount of high-temperature silicone sealant over it and allow it to dry completely. This hole will be your inoculation port. Next, insert a small amount of polyfill found in the pillows into the bigger hole. This will provide the mycelium with all the necessary breathing room as it navigates its way through the grains.

Cooking

Once the grain is nice and hydrated gently simmer them on the stovetop. This step serves to fully hydrate the grains and render them tender, making them favorable for the fungi culture. Simply simmer the soaked grains on the stove for approximately 15 minutes. It’s crucial not to overcook them, as extended cooking can lead to grain cracking and the development of mushy grain spawn. Once cooked, place the grains in a sink with a drain cover. Over the course of about an hour, the grains will drain naturally. After this, you can proceed to fill your jars.

Sterilization

Once you’ve filled your jars with grain it’s time to sterilize it. Sterilization is a necessary step that will eliminate all undesirable contaminants present in the grains that could potentially outcompete your mushroom culture. Therefore, investing in a good pressure cooker is always a good idea in the world of mushroom cultivation.

After filling the jars, envelop the lids with aluminum foil to prevent water from dripping into them. Subsequently, proceed to pressure sterilize the jars for approximately 90 minutes at 15 psi.

Inoculation

Once the sterilization is finished and the grain cooled down to room temperature, it’s time to inoculate the jars. Clean the jar lid with rubbing alcohol, take your liquid culture syringe, and flame-sterilize the needle every time before you insert it through the silicone seal on the injection port. This process should be done under a laminar flow hood or a glove box for an extra layer of security.

Colonization

Once the jars have been inoculated, place them in a warm, dim, and adequately humid setting for a span of several days. Occasionally monitor their progress to observe mycelium growth and ensure no contamination has emerged.

If the jar is contaminated you will see green or brown discoloration on the spots where mold is growing. This could mean that the jars weren’t sterilized properly or that the culture is compromised. Within 1 to 2 weeks, your jars will be completely colonized. Good job, you just learned how to make mushroom grain spawn!

How to Make Mushroom Grain Spawn In Bags

Making mushroom grain spawn in bags is yet another simple and straightforward method. To start you will need sterilized grains, water, sealing bags, and a pressure cooker. An atmospheric steam sterilizer can also be used if you possess more advanced equipment.