Mushroom Box Kit

Begin growing your Mushroom Box Kit today!

Mushroom Box Kit Growing Instructions

Here is a comprehensive grow guide on how to grow elm or blue oyster mushrooms using one of our Mushroom Box Kits. Be sure to scroll down the entire page to to view all of the mushroom growing instructions as well as our mushroom growing video tutorial. Read all instructions before starting!


 Step 1: Cut the bag

Instructions Step 1 for Mushroom Box Kit

Remove the humidity tent, mister, and instructions from the box. Read all instructions carefully before beginning. Punch out the perforated window on the front of the box. Using a knife or scissors, gently slice a “+” into the mushroom block bag the entire length and width of the box’s window, but do not slice into the mushroom block.

Step 2: Place the kit in an ideal location

Place the grow box on an easy-to-clean, water-resistant surface in indirect sunlight: either indirect natural sunlight, fluorescent, or incandescent light. Do not place kit in direct sunlight or in a dark area, like a cabinet or closet. Light that is sufficient to read by is sufficient for the mushrooms to grow. Keep your kit between 60° F and 80° F; otherwise mushroom production might not occur. Choose a location for your kit that you frequently pass by so you will remember to mist it.

>IMPORTANT: Once you cut your mushroom bag open and set your kit in an ideal location, try not to move, shift, or jiggle the kit. Doing so may delay the fruiting of your mushrooms because the mycelium senses “danger” and holds back. If this happens, don’t worry- just leave the kit perfectly still and it will begin fruiting when the mycelium deems the environment to be “safe” again.

Step 3: Cover the kit with the humidity tent Place Humidity Tent on Mushroom Box Kit

Cover your kit with the humidity tent. This is the clear long plastic bag with many ó inch holes. This bag will be used to maintain humidity and moisture and to allow for some air exchange through the holes. “Fluff” the bag (poof it out), then roll the open end of the bag up 3-4 times (much like you would a pant leg) so that the top of the tent is about 6 inches above the top of the block when covered. Place the humidity tent over the block and arrange so there is space on all sides between the block and the tent.

Step 4: Mist

Misting Mushroom Box Kit

Misting is very important, as mushrooms need humidity to grow. Use the mister to mist the inside of the humidity tent with nonchlorinated water 2-3 times per day. (fig. 3) Dechlorinated tap water or well water works fine, but do not use distilled water (which lacks minerals) or rainwater caught from a roof or gutters (which contains many contaminants). To remove chlorine from tap water: fill a pot with tap water and let it sit out, uncovered, for 24 hours or boil the water for 10 minutes, making sure the water has cooled to room temperature before using. After each misting, immediately replace the humidity tent back over the block. There should always be condensation droplets on the inside of the humidity tent. If not, mist more often.

>NOTE: If you live in a dry climate or are not able to mist your tent enough during the day, try putting a glass of water under the humidity tent and/or setting up your kit close to a small humidifier.

Step 5: Watch your mushrooms grow!

In approximately 7-14 days, mushrooms will begin to form where the bag has been cut. Your mushrooms will grow rapidly, even doubling or tripling in size each day.

Step 6: Harvest, eat, and enjoy! 

When To Harvest Oyster Mushrooms

The mushrooms should be ready to harvest in approximately 3-5 days after you see the first mushrooms begin to form. When the cap of the largest mushroom in the cluster begins to turn from convex (turning down at the edges) to concave (flattening out or turning up at the edges), pick the whole cluster. Oyster mushrooms grow in clusters consisting of multiple mushrooms, and it is generally best to pick the entire cluster when you see that the largest mushrooms in this cluster are ready to harvest. If you see a white powder on the side of the bag, the mushroom is simply dropping its seeds. Harvest immediately, eat, and enjoy.

>NOTE: For more information, go to When to Harvest. Also, remember to always cook your mushrooms before eating.

Step 7: Grow more mushrooms! 

To obtain a second flush (another round of mushrooms), let the block sit uncovered in its bag (but not under the humidity tent) for 7 days. Then soak the mushroom block by submerging it under water in a large pot or bucket for 4 hours in non-chlorinated water. (See Step 4 for how to remove chlorine from water.) You will need something to weigh down the block to keep it from floating. After soaking the mushroom block for 4 hours, drain the excess water completely from the bag. If you notice any standing water in the bottom of the bag, drain it again. Repeat the growing process starting with the instructions at Step 2. Most of the time you will get a second flush of mushrooms, and occasionally you can grow a third flush. When your kit is finished. You will know when your kit has finished producing when you see no mushroom growth at all. Once the mushrooms have completely finished growing from the block, you can either compost it (the broken down substrate is a rich and nutritious addition to any compost pile) or reuse your spent kit to grow even more mushrooms on your own substrate, such as coffee grounds or tea leaves!

To learn how to reuse your kit to grow more mushrooms on your own substrate, go to How to Extend the Life of a Spent Kit. In either case, save your reusable humidity tent and sprayer for your next kit! Order your refill kit online.