B+ XL Mycelium box (2100 ML)



This B+ XL mushroom kit is an improved mushroom kit with 80% more substrate than our medium sized mushroom kits. The B+ is probably the best known (mexican) strain and is in our top 3 best selling strains.

This XL mushroom box contains the mycelium of the Psilocybe cubensis 'B+' strain. The B+ mycelium is colonized on a substrate of rye and perlite. The top layer is covered with vermiculite.

Our online manual for the mushroom mycelium kit can be viewed at www.mushroomgrowbox.org.

Holding the double of the substrate, meaning the double of the expected B+ mushroom yield, the XL-Mycelium box is an enhanced product allowing the formation of exceptionally big B+ mushrooms in an exceptional short amount of time. Growing massive magic mushrooms at home has never been easier

This new B+ XL kit highly reduces the probability of contamination and its simplicity of processes will allow you to better focus on the amazing formation of the magic mushrooms. The XL kit is made with the strongest mushroom strains, growing mushrooms was never easier and more reliable.


If you do not want to start growing immediately after receiving the mushroom kits, the best place to store them is your refrigerator (not your freezer!). Do not store them longer than 2 months.

Mushroom Stopper - Bad Trip Stopper

If this will be the first time you use magic mushrooms, make sure that a sober friend is around to help you out in case you feel uncomfortable, sick or scared. Click here to buy our Mushroom Stopper. Our Mushroom Stopper, it helps you to get out of your trip.


We do NOT ship to countries outside the E.U.

If in doubt, please contact us and we will inform you if we will ship these XL mushroom boxes to you!!!

Additional Information

Step 1
Wash your hands thoroughly and clean the outside of the grow kit with a clean, damp cloth. Remove the lid, but keep it for step 3.

Step 2
Take a clean fork and make some holes in the top layer. Divide the holes regularly on the grow kit (6 to 8 rows of holes is enough). This allows the substance absorb the water better.

Step 3
Fill the kit with warm water up to the edge of the kit(20 º C). Place the lid and let the grow kit soak for 2 to 4 hours (Max 12 hours).

Step 4
After soaking, remove the lid of the grow kit and carefully pour off the water.

Step 5
Add warm water (20 º C) to the grow bag.
- For the 2100cc grow kit: 2 cups (0,5 liters)
- For the 1200cc grow kit: 2 cups (0.5 liters)
- For the 250cc grow kit: 1 cup (0.25 liters)
Put the grow kit in the grow bag. Make sure the water does not go over the edge of the grow kit.

Step 6
Close the growing bag by folding the top of the bag and secure it with two paperclips (part of the grow kit package).

Step 7
Put the grow kit in a place out of direct sunlight or under a lamp and not on or near a heater or heat source. The ideal temperature is between 20 and 25 º C. Make sure there is sufficient sunlight.

Step 8
Moisten the kit daily with a spray bottle. This is also important after harvesting.

Step 9
The first mushrooms will be visible in 10 to 12 days.

Step 10
The mushrooms should be harvested just before the skin underneath the hats starts to loosen up.
The harvest: grab the stem gently and turn the mushroom to the left and than to the right and gently pull. This way you can remove the mushroom as complete as possible. This way you can reuse the grow kit.


new flight
After harvesting, clean the surface of the grow and remove the old and dead mushrooms, so the new mushrooms have the ability to grow. Put the grow kit for the best results in the refrigerator overnight. Caution! Not colder than 2 ° C.

Start again from step 5 for the next harvest.

The ideal climate is 22 º C.
When you see the pinheads, put the kit overnight in a cool place, for example in a barn. The drop of temperature causes the mushrooms to get the idea that autumn is coming. Because of that, the mushrooms will grow faster so you can yield earlier.

Reviews (2)
B+ XL Mycelium box (2100 ML)
Review 1 to 2 (of 2 reviews) Result: 1
I have tried almost all of the strains on this page, and this is the fastest growing one. The only thing I dont like about it is a bit lesser potency. Good if you dont like waiting much.
Evaluation: [out of 5 Stars]
very fast delivery.mycelium in excellent condition.
Evaluation: [out of 5 Stars]

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