Grain spawn is an essential ingredient in mushroom cultivation, as it provides the fungi with necessary nutrients and moisture to flourish. The type of grain used and the preparation process are vital aspects to ensure successful mushroom growth. This article aims to detail the process of preparing mushroom grain spawn with a particular focus on whole oats, which has been found to be quite successful and relatively easy to use.
Selection of Grain
The first step in preparing your mushroom grain spawn is to choose the type of grain you want to use. There are numerous options available, but for this guide, we will focus on using whole oats, due to their availability and cost-effectiveness. Whole oats have been found to be highly successful for cultivating various types of mushrooms, making them a preferred choice for many cultivators.
Types of Grain
- Whole Oats: Easy to use and widely available, whole oats are a popular choice for mushroom growers. They have a great capacity to retain water and are quite cost-effective.
- Millet: This small-sized grain provides a large surface area for mycelium to colonise. Due to its small size, it spreads well in substrate and offers quicker colonisation. This is Rootlab’s favourite grain.
- Rye Grains: They are one of the most commonly used grains due to their nutrient content, water-holding capacity, and the ease with which mycelium colonises them.
- Wheat Grains: Wheat is a fantastic medium for mycelium growth due to its nutrient-rich nature. It’s particularly popular for growing gourmet mushrooms. Watch out through if you soak it for a long time, they get mushy.
- Barley: Barley is often chosen for its high nutrient content and its ability to retain water well.
- Corn (Maize): Corn is used due to its availability and affordability, though it may not have as many nutrients as some of the other grains.
- Sorghum: Also known as Milo, this grain is often used in mycology for large scale production.
- Brown Rice: brown rice is another good option due to its nutrient content, People who consume mycelium and Fruiting body in their supplement.Brown rice is a perfect option.
Each grain type has its own pros and cons, so it’s beneficial to experiment and find out which works best for your specific needs.
Soaking the Grains
After selecting your grains, the next step is to soak them. This process helps in hydrating the grains, a crucial element for mushroom growth. Depending on the climate in your area, the soaking time may vary between 12 to 36 hours.
In cooler climates, soaking the grains for a longer period is advisable, while in warmer climates, a shorter soaking time would suffice. There’s no need to fret too much over the exact duration, but it’s crucial to ensure the grains are adequately hydrated before moving on to the next step.
Approximately 600 g of dry grain is typically needed to produce 1 kg of hydrated grain after soaking. However, this can vary depending on the type of grain. For example, brown rice and rye require about 750 g of dry grain to yield 1 kg wet, while millet needs around 850 g. If you determine the exact dry-to-wet ratio for any other grain, it’s a good idea to note it down for future reference.
Draining the Grains
Once the grains have soaked for the required time, they need to be thoroughly drained. A colander works well, though alternatives like a mesh drawer or similar setups can be just as effective — the key is to remove all excess water.
For a DIY option, you can create your own strainer using a milk crate, zip ties, and a roll of sunshade cloth. This setup is durable and cost-effective; just replace the cloth every few months if it becomes discoloured.
⚠️ Tip: Once you’ve used the strainer, make sure to empty it completely — leaving grains behind can attract birds or pests and damage the mesh.
Loading the Spawn
After your grains have been soaked and drained, the next step is to load your spawn into bags or jars — this is where the actual cultivation process begins. Some grains, like rye and brown rice, may need to be boiled for about 30 minutes to soften their hard outer shell, making it easier for the mycelium to colonize. At Rootlab, we boil rye and brown rice, but millet is only soaked.
When filling your containers, be sure to evenly distribute the grain spawn, leaving enough airspace for mycelial growth. For example, a WA mushroom bag is typically filled to 60% of its capacity and never overfilled. This ensures adequate headspace for gas exchange and provides room to break and shake the bag after colonization.
At this stage, it’s also common to sprinkle a bit of gypsum and calcium carbonate into the grain to support healthy growth.
Sterilisation
The final step in the preparation of mushroom grain spawn is sterilisation. Sterilising your grain spawn is a critical process that eliminates any potential contaminants that could hinder the mushroom’s growth. The sterilisation process usually takes between 1.5 to 3 hours. The exact duration depends on the size of your bags or jars; larger containers will need a longer sterilisation time.
Conclusion
While there is an array of techniques available for preparing grain spawn, each with varying degrees of complexity, we’ve found this method to be the most efficient and user-friendly. Based on my experience, this approach strikes a balance between simplicity and quality, demanding minimal time and energy without compromising the desired results. It’s the optimal strategy for those seeking to prepare high-quality grain spawn in an accessible, straightforward manner.
Ofcourse, for those who might find the process of preparing grain spawn too complex or time-consuming, there’s a convenient alternative. We offer high-quality, ready-to-use mushroom spawn or pre-sterelised grain bag for purchase. This allows you to focus more on the exciting part of mushroom cultivation and less on the prep work, making the journey smoother and more enjoyable.
