Do you like to cook with white button or cremini mushrooms? Then you will love chestnut mushrooms. Chestnut mushrooms (Pholiota Adiposa)look almost identical to the white button and creminis, except that they have tan-colored tops and much better texture and flavor compared to their counterparts.
Unlike other fungi varieties, they retain an asparagus-like snap to them after cooking. They have a distinct nutty flavor that is reminiscent of shiitake mushrooms. Throwing a handful of chestnuts into your stir-fry is an instant way to add pizzazz and turn a simple meal into a gourmet feast.
One of the interesting things about these fungi is their ability to grow on both live and decaying wood. This makes them both parasitic and saprophytic, although you’ll mostly find them growing on live beech trees.
If you would rather skip the hunting part of the process, you can grow your chestnut mushrooms right in the comfort of your home. Here’s how to go about it.
How to Grow Chestnut Mushrooms
Mushrooms in the wild thrive under very specific conditions. The idea is to mirror these conditions and replicate the same outcome in a controlled setting. If there is too much light, not enough humidity, or extreme temperatures, they just won’t grow.
Likewise, if the conditions change somewhere along the growth cycle, the entire mushroom-growing project will be a bust. So, keep this in mind when you start the project.
Step 1: Obtain the Mushroom Spawn
The first step involves getting your hands on the chestnut mushroom spawn or spores. Spores are the “seeds” or reproductive bodies of mushrooms and are typically harvested from the underside of the mushroom cap.
Each spore has all the necessary elements required to form new fungi. As the spores germinate, they begin to create a network of cells collectively called the mycelium. This mycelium is then transferred onto a substance that supports and promotes their growth – the substrate. The entire structure (mycelium plus substrate) is referred to as the spawn.
Step 2: Choose Your Substrate
Simply put, the substrate is the growing medium — or “soil” — that you will use to grow your mushrooms.
There are three principal types of substrate that growers commonly use to grow Chestnut mushrooms. Depending on how you choose to buy your spawn, it will generally already be in the substrate:
This is sterilized sawdust that’s inoculated with chestnut mycelium. It is ideal for outdoor mushroom beds and logs.
The main advantage of using them is the fact that they have many more inoculation points when transferred onto a suitable substrate. This is in large part due to the small and numerous sawdust particles.
This uses sterilized grain in place of sawdust. The most popular types of grain used with mycelium cultures include millet and rye, although you can use wheat, corn, and other different kinds of cereal grains.
Since grain is more nutrient-rich compared to sawdust, it is an excellent choice if you intend to grow your mushrooms indoors.
If you plan to use fiber or wood substrates, plug spawn is your best bet. It readily colonizes logs, wood stumps, and even cardboard. Plug spawn can be made from a collection of live mushroom stems or small wooden dowels that have been inoculated with mycelium.
Betterfungi Chestnut Mushroom Spawn Plugs. I have had good luck with this product. The package comes with 100 plugs, and almost all of mine grew into healthy chestnut mushrooms.
Step 2: Introduce the Spawn to the Substrate
This step is also known as inoculation. It is when you introduce your chestnut mushroom spawn onto your substrate. As mentioned above, if you’re using a growing kit, the substrate will generally come already colonized with the chestnut mycelium. So, all you’ll need to do is:
- Take the plastic-wrapped substrate block out of the cardboard box.
- Cut a 6-inch slit through the plastic bag with a sharp knife to expose the substrate.
- Place it cut-side-down in a bowl filled with water and let it soak for about 1 to 2 hours, depending on the size of the block.
- Place the block back in the cardboard box, with the slit side exposed to the outside elements. The box should have a window to allow air in.
If you’re an experienced grower and don’t want to use a grow kit, or if you’re feeling particularly adventurous, then you can buy spawn separately, choose which type of substrate you would like to use, and then inoculate your substrate yourself.
We recommend using sawdust, at least the first time you try out this process, as it is the easiest substrate to inoculate properly.
We also know a grower who claims to have had success using a substrate made from potting soil, peat moss, and compost. To use this method, add equal parts sterile compost, potting soil, and peat moss in a container. Then add the chestnut spores to the surface of the soil and water the mixture to make it moist. Cover with clear plastic wrap and poke holes on the surface to create air passageways.
Your mushroom spawn will usually come with inoculation instructions, which we recommend that you follow.
Step 3: Incubate the Spawn
The next step is the incubation phase. Here’s what you need to do.
- Place the inoculated substrate in a dark area
- Mist it with water every day to keep it moist
- Don’t expose it to direct sunlight
- Keep the temperatures between 60°F and 80°F
During incubation, the mycelium completely colonizes the substrate. The process could take anywhere between a couple of weeks to a couple of months. By the end of it, you should see a solid white mycelium mat coating its surface. This means that it’s ready for fruiting.
Step 4: Place Substrate Into Fruiting Conditions
After a few days, you’ll notice mushroom pinheads forming on the surface. These are what eventually grow into full-sized chestnut mushrooms and take 7 to 10 days to mature after you first see the pins.
At this stage, you will need to ensure that the mushrooms have adequate airflow. Mushrooms produce carbon dioxide, and will suffocate if they don’t have enough air.
Chestnut mushrooms do need moisture to grow. If the location in which you are growing your mushrooms is very dry, then consider using a plastic garbage bag as a humidity tent. Make sure that you slice some holes through the plastic to allow for adequate ventilation.
Step 5: Harvest Your Chestnut Mushrooms
Your mushrooms should be ready a week or so after the pinheads have formed. To harvest the mature chestnut mushrooms, gently twist or pull them away from the substrate they’re growing on. Be careful not to pull out too much soil to allow for more mushrooms to sprout from it.
In another week or two, you’ll have a new crop ready for harvesting. The subsequent harvests will continue to decrease as you exhaust the substrate. At that point, you’ll either need to purchase a new growing kit or create a new spawn.
Easy, Convenient, Safe
The best thing about growing your own chestnut mushrooms is that you don’t run the risk of consuming poisonous fungi when hunting for them in the wild. Besides, it’s a convenient alternative to foraging through the forest in search of them. Use the steps detailed in this guide to start growing your own.
Once you have some chestnut mushrooms to cook, then check out our article, Five Delicious Chestnut Mushroom Recipes to Try.