5 Steps to Grow Mushrooms in a Monotub

Mushrooms are a great addition to any home, and growing them in a monotub is an easy and effective way to do so. A monotub is a simple container used for growing mushrooms, which can be made from a variety of materials including plastic tubs and shoe boxes. With a few basic supplies and a little bit of patience, anyone can grow their own mushrooms at home.


Myterra Labs has made mushroom growing even easier with the Monotub Mushroom Grow Kit. Leave the guesswork out of the equation and experience a quality, tested kit that is designed for optimum yields and easy growing. The kit provides everything you will need to start growing your favorite strain of mushrooms. Click here to view this easy-to-use monotub grow kit.



What is a monotub?

Monotub style growing is a horizontal style of growing mushrooms, similar to the style of growing used for button mushrooms and portobellos, except that the growing surface is enclosed in a container.

A monotub consists of the following elements: a container to hold the growing medium, also known as the substrate, and a lid to cover it. Plastic tubs work well for this purpose, as they are readily available and easy to work with. Plastic tubs will need to be modified by drilling holes into the plastic lid and base to provide your mushrooms with adequate air exchange.

Myterra Labs monotub mushroom grow kit includes a Max Yield Bin, which has pre-drilled holes - positioned for optimal airflow and a set-and-forget style of growing. Max Yield Bins' new V2 tapered lid further enhances your growing experience with the sloped sides, which transfers moisture away from your growing surface to prevent condensation droplets from falling on your mushrooms. Click here for more details.



What will I need to grow mushrooms in a monotub?

Myterra Labs easy to use grow kit contains everything you need to grow mushrooms in a monotub and can be purchased by clicking here

If you already have a monotub, then you will need some substrate (soil used to grow mushrooms) and grain to make mushroom spawn. We highly recommend the Re-Up bundle which contains 2 bags of manure-free, vegan substrate and 1 bag of organic rye berries. Click here to get Myterra Labs Re-Up bundle.


The last things you will need are:

  • Your favorite mushroom strain in liquid culture or on an agar plate. We do not recommend using spores directly onto grain because spores have a high probability of containing hidden contaminants. Instead, grow your spores on an agar plate first to ensure a clean culture.
  • 70% isopropyl alcohol in a spray bottle
  • Latex gloves - highly recommended, but not required
  • Micropore tape (included in Myterra Labs Mushroom monotub kit)

 Now that you have everything you need, let's start making a monotub.


STEP 1: Inoculate Grain

Inoculation is the step of adding a living culture to a growing medium. In this case, you will be adding your mushroom culture to your grain bag. We recommend using liquid culture to inoculate the grain bags if you do not have a sterile environment to work in. If you have a laminar flow hood or still air box, using an agar culture to inoculate your bags is a viable option. The choice is yours and we will cover both methods.

(a) Liquid Culture

Remove grain bag from outer packaging. Wipe a section of the bag that covers the grain with 70% isopropyl alcohol. Attach injection port to same area (all Myterra Labs grains include an adhesive injection port inside the outer packaging). Wipe injection port with alcohol. Inject culture. Place bag on a shelf out of direct sunlight.



(b) Agar Culture

Refined In The LabRemove grain bag from outer packaging. Wipe the outside of the bag with 70% isopropyl alcohol. Place the bag in a sterile environment (in front of a laminar flow hood or inside a still air box). Cut the top of the bag off with a sharp, clean knife that has been sprayed with alcohol. Prop the bag open. Sterilize your scalpel with alcohol and a flame (or loop sterilizer). Open your agar culture and place the blade tip into an uncolonized piece of agar to cool the blade - this process can be repeated until the blade has cooled. Cut the agar plate into multiple pieces with your scalpel - the more pieces of agar, the more inoculation points you will have.


Carefully transfer the agar wedges into the open grain bag using the tip of the scalpel. Once all pieces have been transferred, seal the bag and shake the bag to distribute the agar pieces throughout the grain.


 STEP 2: Grain Spawn

Shake the bag when you see healthy white growth of mycelium - typically after 7 days. Shake thoroughly and break up any clumps of grain. Replace the bag back onto the shelf where it was being stored. Wait until the grain bag is completely white - typically 1-2 weeks. Once the bag is completely white and colonized, you will have successfully created a bag of grain spawn. Keep an eye on your grain spawn and watch out for any discoloration, which could be a sign of contamination. If your grain spawn is contaminated, you will need to make a new spawn bag - the contamination will only grow larger if you decide to use it.


STEP 3: Prepare Your Monotub

Place micropore tape over all holes in the monotub lid and base. Spray and wipe your bin and liner with 70% isopropyl alcohol. Lysol can be used as an additional tool to remove any possible contaminants, but it must be allowed to sit on the surface of the bin for at least 10 minutes before wiping it out of the bin and applying alcohol. 

Remove substrate bags from outer packaging. Spray and wipe the outside of your spawn and substrate bags with alcohol.


STEP 4: Inoculate Substrate

Next, you will need to inoculate the substrate with the mushroom spawn. This process should be [erformed in a clean area with very little air movement, but preferably in front of a laminar flow hood or in a large still air box. We recommend using gloves for this process, but it is not a requirement. Rub 70% isopropyl alcohol over every surface of your gloves.

Cut open the tops of all bags with a clean knife that has been sprayed with alcohol.  Pour spawn into bin. Pour substrate bags into bin - retain 1/4 of a bag for a casing layer. Mix thoroughly by hand. Pour remaining substrate evenly over mixture. Press down lightly to flatten surface. You can also use a trowel that has been sprayed off with alcohol to get a perfectly flat surface. Replace the bin lid. Once the substrate is inoculated, it is important to keep the container out of direct sunlight and at room temperature to allow the mycelium to grow. Mycelium is the network of branching, thread-like structures that make up the body of the mushroom.


STEP 5: Set-And-Forget

Over the next couple of weeks of incubation, you should start to see the mycelium spreading throughout the substrate. At this point, the mycelium will be needing fresh air and high humidity to form mushrooms. The micropore tape over the holes in the bin will allow fresh air to flow in and out of the bin while preventing contaminants from entering and will retain the humidity inside the bin. Don't be afraid to open the bin and take a peak inside the monotub once the entire surface has white mycelium poking through.

Over time, you should start to see pins, which are small, white bumps that will eventually develop into mushrooms. It is important to maintain the humidity within the container to ensure that the mushrooms grow properly - leave the lid on the monotub. 

Approximately 3 weeks after inoculating the substrate, your mushrooms should be ready to harvest. You can do this by gently twisting the mushroom stem until it breaks off, being careful not to damage the mycelium or any other mushrooms nearby. You should also be sure to clean and sanitize any tools used to harvest the mushrooms to prevent contamination.


Harvest your mushrooms when the veils are still in tact. The veil is a thin membrane that connects the cap to the stem and covers the gills on the underside of the cap. The image on the left shows a mushroom with its veil intact, surrounded by mushrooms that have lost their veil. The veil will develop a more cobweb like appearance before it releases from the cap. Once this veil breaks, the mushrooms will release a lot of spores, which can form a dark inky surface on top of your mushrooms - not ideal. The more mushrooms you grow, the more comfortable you will become with identifying the perfect harvesting stage.




Growing mushrooms in a monotub is a great way to add a unique and tasty addition to your home. The process is easy and can be done anywhere, from a small apartment to a large backyard. With a little bit of patience and the right supplies, anyone can grow their own mushrooms at home. Not only is it a fun and rewarding hobby, but it also provides a great source of fresh and nutritious food. So why not give it a try and start growing your own mushrooms today?