My latest indoor gardening adventure is growing mushrooms indoors. Mushrooms are quick and easy to grow indoors. They are a nutritious food that is high in selenium and potassium.

Way back in the day, I worked at an organic gourmet mushroom farm where we grew oyster and shitake mushrooms in bags of straw that hung in a greenhouse. Now I am just growing them on a smaller scale.

This article will focus on growing oyster mushrooms indoors but these methods also work well for shitake.

Easiest Mushrooms to Grow Indoors

Oyster mushrooms are (in my opinion) the easiest mushrooms to grow indoors. They are hardy and not as picky about growing conditions as many species.

The Pearl and Blue oyster varieties are considered the easiest to grow. The yellow and the pink, while spectacular to look at, are a bit pickier.

Growing oysters on top of my fridge. Photo by Ame Vanorio

Growing Conditions

Light

It’s a misnomer that all mushrooms like the dark. Some mushrooms such as oysters need indirect light to grow. Button mushrooms prefer a darker area. Make sure you know the light requirements for the variety you will be growing.

Humidity

Mushrooms like humidity and so misting is a common way to add extra moisture. Fill a spray bottle with distilled water and mist morning and evening.

Water

If you start from scratch you will soak your medium before adding the mushroom spore. Otherwise, we typically mist versus directly watering the grow bags.

The Perfect Spot

Sometimes finding the perfect spot to grow mushrooms is the hardest decision. I started with mine sitting on the top of the refrigerator. However, that spot didn’t offer them enough humidity.

So I moved them to a shelf near the bathroom sink. This spot is a tad cooler and offers a bit more humidity.

Also since it’s in the sink area I don’t have to worry about spraying a mister around.

Buying a Kit

For my first foray back into mushrooms I decided to go with a kit. I choose a kit from True Leaf Market because I purchase their microgreen kits and have been happy with their quality.

A kit is a good way to get introduced to mushrooms and get some practice.

When you buy a kit, the first steps have been done for you. The bag is well colonized and ready to grow mushrooms.

Check out my video on my experience growing oyster mushrooms from a kit. Includes a cooking example.

Growing From Scratch

You can also purchase mushroom spawn and mix it with the medium of your choice. This may be straw, sawdust, hardwood logs, or compost.

Steps to growing oyster mushrooms from scratch

Purchase spawn from a mushroom grower such as Fungi Perfecti.
Purchase chopped straw or manually chop straw into 1 - 3 inches in length.
Moisten and sterilize the straw to kill any competing organisms. You can do this by placing it in water and bringing it to a boil for two minutes. You can also place it in a bowl with a small amount of water and microwave it on high for three minutes.
Let the straw cool enough so you can handler it but while it’s still warm.
Mix your spawn in with your straw. Refer to the directions for the amount to use.
Stuff the inoculated straw into a plastic bag
Use scissors to cut three small X-shaped holes on the top side of the bag.
Place the bag in your growing location.
It will take several weeks for the mycelium to start growing and spreading through the bag. You will notice this white growth as it spreads and gets thicker.

Common Mushroom Problems

Mold

Mold is the most common problem because it also likes a cool damp growing environment. This is one reason it’s important to heat treat your substrate before introducing spawn.

Mold organisms can also enter the growing substrate from your home.

If you notice spots of green or yellow/brown mold, carefully cut them out of the substrate.

If you are having an issue with mold growing increase your airflow by adding a small fan to the space. Air circulation will reduce mold growth.

One Flush and Then Nothing

Another common problem is when the mushrooms make one flush and then stop producing. Sometimes it helps to “shock” the mushrooms into thinking there has been a weather change. Fill the kitchen sink with very cold tap water.

Next, dunk your mushroom bag into the water and let it soak for one hour. Drain the water and let the bag drip dry before you place it back in its location. This often stimulates another flush.

Harvest

Once your mushrooms appear they will grow quickly and be ready to harvest in just a few days. So keep an eye on them!

Harvest oyster mushrooms when they are several inches and the caps have started to flatten out.

Have more mushrooms than you can eat. Store them in a paper lunch sack in the refrigerator for up to two weeks. You can also dehydrate them for later use.

I love growing microgreens!

Recycle Your Spent Spawn

After you have gotten several flushes from your bag it’s production will slow down. You can give your mushroom spawn a new life by adding it to garden compost.

This will add nutrients to the compost and you may get some mushrooms to harvest.

In addition, if you raise worms, they will love to eat the spent contents and turn it into compost for you.

Author, Ame Vanorio, is the director of Fox Run Environmental Education Center. Ame recently moved from a rural farm to an urban apartment. Join her as she documents this new adventure!