When I first thought about growing mushrooms indoors, button mushrooms were an obvious choice. They’re the classic mushroom that you find in almost every grocery store, and they’re surprisingly easy to grow at home.
Whether you have a little space or just want to try something new, button mushrooms are a great place to start. Plus, once you have them growing, you’ll always have fresh mushrooms on hand for all your favorite dishes.
Here’s how I grew mine indoors, step by step.
Why Grow Button Mushrooms?
Button mushrooms are the kind you’ve probably eaten a thousand times—smooth, white caps with a mild flavor that goes with pretty much anything.
But what I didn’t realize before I started growing them is how much fresher and tastier home-grown mushrooms are.
The best part? They grow in compost, which makes them incredibly easy to cultivate in just about any space.
Another reason I chose button mushrooms is their versatility.
Whether I’m sautéing them for a stir-fry, adding them to a salad, or stuffing them with cheese, they never disappoint.
They’re also packed with vitamins, minerals, and antioxidants, making them a healthy addition to my meals.
What You’ll Need to Get Started
Growing button mushrooms indoors doesn’t require a lot of fancy equipment, which was a huge plus for me when I was just getting started. Here’s what you’ll need:
- Substrate: Button mushrooms grow best in compost or manure-based substrates. I used a pre-mixed compost substrate, which you can find online or at gardening stores.
- Button mushroom spawn: You can easily buy mushroom spawn from a supplier.
- A tray or container: I used a shallow tray with small drainage holes to hold the substrate.
- Spray bottle: To keep the substrate moist.
- A dark, cool space: Button mushrooms prefer cooler temperatures and low light, so a basement or closet works great.
Step-by-Step Guide to Growing Button Mushrooms Indoors
Step 1: Preparing the Substrate
Button mushrooms need a rich, nutrient-dense substrate to grow, and compost is ideal for this.
I went with a pre-made compost substrate to make things easier.
If you want to make your own, you can mix straw with manure and compost, but it’s a bit messier.
The pre-made option saved me some time and hassle.
Once I had the substrate, I spread it evenly in a shallow tray, making sure it was about 3-4 inches deep. The depth is important because it gives the mushrooms enough space to establish their mycelium and grow properly.
Step 2: Inoculating the Substrate with Spawn
Next, I sprinkled the button mushroom spawn evenly over the surface of the substrate. Think of this as “planting” the mushrooms—except instead of seeds, you’re using spawn, which is a bit like mushroom seeds that have already started growing.
After spreading the spawn, I mixed it lightly into the top layer of the substrate, making sure it was well incorporated but not buried too deep.
Then, I misted the entire surface with water to keep it moist. This step is key because mushrooms thrive in damp conditions.
Step 3: Incubation and Colonization
Once the spawn was mixed into the substrate, I covered the tray with a piece of damp cloth to help retain moisture and kept the tray in a cool, dark space (around 16°C to 20°C or 60°F to 68°F).
Button mushrooms love the cold, which is why they grow well in basements or cooler areas of the house.
Colonization takes about 2-3 weeks, and during this time, the mycelium spreads through the substrate.
I checked on it regularly to make sure the cloth stayed damp, but otherwise, there wasn’t much to do except wait. It’s a bit like watching paint dry, but way more rewarding.
Step 4: Casing Layer and Fruiting
Once the substrate was fully colonized, I added a casing layer to help the mushrooms start fruiting.
The casing is a layer of peat moss and vermiculite that helps keep the humidity high.
I spread a thin layer (about 1 inch) of this mixture over the surface of the tray.
Then, I moved the tray to an area with a little more light (but still indirect).
I kept misting the tray daily to make sure the casing layer stayed moist.
Within 1-2 weeks, small white pins (baby mushrooms) started to pop up through the casing layer. This is when things really get exciting.
Step 5: Harvesting
Button mushrooms grow quickly once they start fruiting.
I harvested them when the caps were still slightly closed but had started to flatten out.
This is when they’re the most flavorful.
To harvest, I gently twisted the mushrooms at the base, being careful not to damage the surrounding substrate.
The best part? Button mushrooms can produce multiple flushes.
After harvesting, I kept misting the tray, and within a couple of weeks, I had a second round of mushrooms ready to go.
In total, I got about three flushes from one tray before the substrate was spent.
Best Practices for Growing Button Mushrooms Indoors
- Cool Temperatures: Button mushrooms prefer cooler temperatures, so keeping the grow space around 16°C to 20°C (60°F to 68°F) is key to success. If it’s too warm, the mushrooms might not fruit as well.
- Moisture Management: Keeping the substrate and casing layer moist is critical. I misted the tray daily to maintain high humidity. You don’t want it soaking wet, just evenly damp.
- Multiple Flushes: Don’t stop after the first harvest! Button mushrooms can produce several flushes, so keep caring for them after your first round of mushrooms.
- Patience: Button mushrooms take a bit longer than faster-growing varieties like oysters, but the wait is worth it. The flavor and freshness of home-grown button mushrooms are far superior to store-bought ones.
Health Benefits of Button Mushrooms
Button mushrooms are more than just tasty—they’re also packed with nutrients.
They’re low in calories but high in protein, fiber, and essential vitamins like B2 and D. In fact, button mushrooms are one of the few plant-based sources of vitamin D, making them a great addition to a vegetarian or vegan diet.
There’s also some evidence to suggest that button mushrooms may have antioxidant properties, which can help protect your cells from damage.
Plus, they’re a good source of potassium, which is important for heart health and maintaining healthy blood pressure.
My Personal Experience Growing Button Mushrooms Indoors
Growing button mushrooms indoors was a bit more of a learning curve than oysters or lion’s mane, but once I got the hang of it, the process was pretty straightforward.
The hardest part was keeping the temperature cool enough in the room where I was growing them.
At first, it was a little too warm, and the mushrooms weren’t fruiting as quickly as they should have.
Once I moved the tray to a cooler spot, they started popping up much faster.
Another challenge was keeping the casing layer properly moist.
I had to adjust my misting schedule a few times to get it just right—not too dry, but not soggy either.
After a bit of trial and error, I found that misting once or twice a day was enough to keep everything in balance.
Overall, growing button mushrooms indoors was a fun and rewarding experience.
The flavor of freshly harvested button mushrooms is so much better than what you get at the store, and the fact that they kept producing multiple flushes made the effort more than worth it.
Plus, it’s a pretty low-maintenance project once you get everything set up.