How to Grow Mushrooms at Home

Having fresh, hand-picked mushrooms available at your fingertips is much easier than most people initially think. By growing your own mushrooms at home, it’s easier than you think. You need a few materials and a dark, cold environment then will grow most of your favorite mushrooms available year-round.

Mushrooms are not a one-size fits all type of organism to grow. The type of mushroom you are growing will determine what substrate is needed to cultivate the spores best. Most common mushrooms grown at home include: 

  • Shiitake
  • White Button
  • Maitake
  • Oyster (many different colors available) 
  • Portobello

The importance of the right growing substrate cannot be understated when attempting to grow mushrooms at home. Like plants, mushrooms have their preferences for their growing medium; if these preferences are not met, they might grow poorly. 

Shiitake mushrooms prefer to grow on hardwood sawdust or wood chip substrate and would not grow well in compost or manure-type substrate. Alternatively, straw works well for oyster mushrooms, and compost or manure is perfect for white button mushrooms. Portobello mushrooms thrive best on a mixture of compost and straw for their substrate. Some grow kits will just have wood chip substrates, while other types of mushrooms require a log to be inoculated with the spores for the best chance of growth. 

While the materials may vary slightly depending on what type of mushroom is being grown, here are the basics of what is needed to grow mushrooms:

  • A cool, moist area to grow: This can be an indoor, climate-controlled area or, if you are attempting to grow outside, an area that stays shaded for most of the day. 
  • Spores: These can be in the form of a liquid suspension in a syringe or in pre-made substrate/spore mixtures called “spawn.” Ensure you are purchasing spores from reputable websites for accuracy and sterile conditions. 
  • Substrate: Types of substrate will vary depending on what is being grown. Compost, manure, straw, woodchips, and sawdust are all common substrates. 
    • Like with spores, you want to take care to sterilize or purchase already sterilized substrates. Growing mediums, like straw, can be sterilized by submerging it in boiling water for up to two hours. 
    • With grow kits, the substrate and spores are already mixed together (mushroom spawn)
  • Containers or trays to place substrate and spores. 
  • Heating mat: This will help maintain a consistent temperature to encourage mycelium development and, later, fruiting. 
  • Gloves to maintain a sterile environment. 

Now that you have all of your materials, your desired spores, and their proper substrate, you can begin the growing process. 

  • Step One: Set up your substrate in a cool room or a cool area outside if growing outdoors. The substrate should be spread into your trays or containers about 6 inches deep in a container approximately 14 to 16 inches long and wide. Using sterile gloves, spread the spores evenly across your growing substrate. Maintain a moist environment by misting regularly throughout the day or covering with damp towels; this is where growing in tote-type containers may come in handy since they often come with a lid. 
  • Step Two: Incubate. For the first 3-4 weeks of setting up your substrate, you will want the temperature to be 70º F or slightly lower. Hotter temperatures than this can damage or kill the spores. A heating pad can be used to maintain this temperature, and set it under your tray or container. 
  • Step Three: The time to lower the heat will come when the tray or container becomes fully developed with mycelium. This appears like white, root-like growths throughout the substrate. The optimum growing temperature to induce fruiting bodies is between 55-60ºF. Allow a further 3-4 weeks for growth before harvesting using sterile tools. Mushrooms such as white buttons are ready to be harvested once the caps are open but can continue to grow to the “cremini” mushroom stage, which is when a white button turns brown. Cut off by the stem, and your growing tray should continue to bear mushrooms for a few months before needing a refresher of fresh spawn. 

Growing mushrooms on an unprepared log can be a bit more time and labor-intensive in the beginning but are necessary to cultivate certain species of mushrooms, such as lion’s mane and reishi. Keep in mind that growing mushrooms in this way can take up to a whole year after inoculation to bear fruit. Here’s how you can inoculate your own log to grow decomposer mushrooms: 

  • Step One: Locate the logs. Find hardwood trees or logs about 4 inches in diameter and up to 3 feet tall. These logs should have intact bark and are best harvested in the dormant season when the sugars are not flowy as freely throughout the tree. 
  • Step Two: Cure the logs. Set the logs in a damp, dark, and cool place for up to a month before beginning the inoculation process. 
  • Step Three: Inoculate the logs. Acquire your mushroom spawn and prepare to drill into the log. Drill about 1.25 inches deep into the log, maintaining at least 4 inches, but up to 6 inches, between each hole. From here, the spawn can be added to the holes. Depending on the type of spawn used, you can hammer in the spawn (plug spawn) or use a specialized tool to insert sawdust spawn into the holes. 
  • Step Four: Plug the holes. The holes filled with spawn are now to be covered with wax, as this will help maintain moisture in the hole and prevent other fungi from colonizing that space. Use soy or cheese wax for this, as these are the most durable against the elements and potential pests. 
  • Step Five: Waiting and Harvesting. This process will take the longest, especially compared to growing other types of mushrooms indoors. Usually, it will take a year for the spores to bear fruit that can be harvested from the log. To keep your log producing flushes of mushrooms for multiple years, do not allow the log to dry out. Otherwise, all the heavy lifting and laborious tasks are done, and yearly harvests are available in your own backyard. 

Mushrooms grown in grow kits will include step-by-step directions, though they’re not too different from growing from scratch once the substrate has been inoculated. Many grow kits simply require the block to be removed from the cardboard box, have some slits cut into the plastic containing the spawn, and keep it moist in an area with consistent temperatures. 

There are numerous ways mushrooms can be attained throughout the season, and most of them don’t involve a trip to the store to get them. Foraging for your own home-grown mushrooms can occur in your backyard or from a cool room in your home, with many different options available to suit each individual’s needs.