How to Grow Mushrooms In a 5 Gallon Bucket

Growing mushrooms can be challenging, but it doesn’t have to be. If you’re looking for a simple, low-cost way to grow mushrooms at home, the bucket method is a great choice. It doesn’t require any special skills or equipment, and it produces high yields of mushrooms.

Growing in a five gallon bucket is also a great way to get even more use out of your Oyster Mushroom Grow Kit! After you’ve harvested a couple rounds of mushrooms from your block, the fun doesn’t have to end. You can break the block up into small pieces and use it as spawn to continue growing.

Whether you’re using an old mushroom block or you have another source of mushroom spawn, the bucket method is a great way to grow a lot of mushrooms in very little space.

What type of mushrooms can grow in a bucket?

Mushrooms that grow on trees in the wild, like Lion’s Mane and Oyster, are great candidates for the bucket method. We want to use mushrooms that feed off decomposing matter and are side fruiting. Mushrooms that grow straight up from the ground will not work for this method. 

In this article, we’ll focus on Oysters, as they’re easier to grow, more aggressive, and less sensitive about growing conditions. Blue Oysters or any other variety of Oyster mushrooms work very well for this style of growing.

What you need to grow mushrooms in a bucket:

• Two 5 gallon buckets with lid (best if they’re new, you’re gonna eat these mushrooms!)
• A drill with a ¼” or ½” bit
• Substrate -  we suggest hardwood chips, sugarcane mulch, sawdust, or straw
• A container big enough to soak your substrate in
• Mushroom spawn or a mushroom block broken up into small pieces (a good ratio is about 2 ½  - 5 pounds of spawn per 5 gallon bucket, or one mushroom block)
• Spray bottle

 

Which type of substrate is best?

There’s a lot of options you could use to grow your mushrooms in. Popular choices include straw, wood chips, sawdust, and sugarcane mulch. You can also add small amounts of moistened cardboard or coffee grounds in with your other ingredients. 

Keep in mind that the main goal is to prevent contamination from other yeasts, molds, and bacteria. This makes some choices better than others. Some substrates will require some sort of pasteurization, so it’s up to you what you are willing to work with. For example, straw can be easily contaminated, so if you choose to use it, consider cold water lime-treated pasteurization.

For the bucket method, it’s also best to choose a light textured substrate that allows the mushrooms to breathe well. If the substrate is too fine-textured, it may become too packed and leave less room for airflow. For these reasons, we recommend hardwood chips, as they’re pretty easy to find and provide a decent amount of breathability.

Steps to growing with the bucket method:

1. Drill holes all around the outside of one of your buckets, about 4-6 inches apart (the holes are for ventilation and also where the mushrooms will be fruiting). Then give both buckets and their lids a nice wash with warm soapy water. Option A: Soak your wood chips in hot water overnight. This will partially pasteurize them as well as hydrate them, which makes it easier for the spawn to take hold. Make sure to let them completely cool. Drain off the excess water. Option B: Soak/fully submerge your woodchips for a week in non-hot water to pasteurize and hydrate your chips. 
   
2. Layer the hydrated wood chips and mushroom spawn in the bucket with the holes. The wood chip layers should be about 1.5” thick with a thin layer of spawn. Put the substrate down first and layer like a lasagna. Layer all the way to the top of the bucket, finishing with a final top layer of substrate.                 
   
3. Place the layered bucket inside the second bucket that has no holes. Put the lid on and place it in a warm, dry place to colonize. It will be happiest at a comfortable room temperature, about 55-75º F. It should take 3-4 weeks for the mycelium to colonize, depending on your environment and what species you’re growing. 
   
4. Lift the inner bucket out when the spawn has colonized the substrate - the oxygen will trigger fruiting!

About a week into colonizing is a good time to open the lid and check to see how things are progressing. As the mycelium grows, it will form white cotton-like growth throughout the growing medium. The substrate will eventually turn completely white with mycelium. By letting it fully colonize, you increase yields and decrease the risk of contamination.

No growth? Strange smell? You may have a contamination problem. This can be caused by too much moisture, contaminated substrate, or too much heat. If you have contamination, you’ll need to start over.   

A few days after you’ve removed the inner bucket, pins will start to form through the holes that you drilled. Pins are baby mushrooms! It’s super important to keep those little pins hydrated, so make sure to mist them a few times a day during this stage. Once those pins start popping out, it’s fruiting time.

 

Fruiting the mushrooms

Move the bucket to a new place to fruit. An ideal location is somewhere out of direct sunlight, and preferably with high humidity. Depending on your conditions, you can do this in a shed, a garage, your backyard, or a deck in the shade. 

You don’t want the mushrooms to dry out, so avoid places that are overly breezy or are in direct sunlight. Mist the mushrooms with a spray bottle a few times a day to help keep them moist, especially when they’re first starting to pin. If you need to increase humidity, you can also drape a plastic bag loosely around the bucket and/or spray near the holes to get them to pin.

Once they start fruiting, mushrooms will double in size every day! It should take about a week for the mushrooms to go from pins to full sized.

When to harvest the mushrooms

Oyster mushrooms are ready to harvest when the fruiting bodies get large and their caps start to flatten out. Cut off the entire cluster with a sharp knife, or use your hands to gently break them off from the growing medium. 

Oyster mushrooms have a shelf life of 5-7 days. Keep them in a paper bag in the refrigerator until ready to use.

Keep those mushrooms growing

You may be able to get a second or third flush of mushrooms from your bucket. After your first harvest, continue to mist the holes daily with a spray bottle. The mycelium should regrow and you can get more mushrooms in a week or two. You can also pull out the myceliated mass from your bucket and sprinkle it in your garden for seasonal fruitings in the summer and fall.