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McKennaii XL Mycelium box (2100ML)



Avalon is proud to present the McKennaii Mycelium XL-Box. This McKennaii XL-MyceliumBox is an enhanced Mycelium box with 80% more substrate (2100 CC). The McKennaii mushroom caps can grow into weird shapes, but get the job done properly.

This XL-MyceliumBox contains the mycelium of the Psilocybe cubensis 'McKennaii' strain. The McKennaii mycelium is colonized on a substrate of rye and perlite. The top layer is covered with vermiculite.

Our online manual for the XL mycelium box can be viewed at www.mushroomgrowbox.org.
There are no paperclips included in the box.

Holding the double of the substrate, meaning the double of the expected Thai yield, the XL-Mycelium Box is an enhanced product allowing the formation of exceptionally big Thai mushrooms in an exceptional short amount of time.

Made for the amateur mycologist, the Mckennaii XL-Mycelium kit highly reduces the probability of contamination and it's simplicity of processes will allow you to better focus on the amazing formation of mushrooms bodies. Made with the strongest redefined thai mushroom strains, growing mushrooms was never easier and more reliable.

Because the kits are fresh we recommend to set them up right away.

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!!!

Mushroom growbox manual


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
Fill the kit with water up to the edge of the kit (20 º C). Place the lid and let the mushroom growkit soak for 12 hours ( if this is your second flush you let the kit soak for 8 hours).

Step 3
After soaking, remove the lid of the grow kit and carefully pour off the water, until the last drop.

Step 4
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 5
Close the growing bag by folding the top of the bag and secure it with one or two paperclips (part of the grow kit package).

Step 6
Put the grow kit in a place out of direct sunlight but enough daylight, 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 7
The first mushrooms will be visible in 10 to 12 days.

Step 8
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.


Enjoy your shrooms!

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 2 for the next harvest.



  • The ideal climate is 22 º C.
  • Work very clean!
  • When using a heating mat, make sure there is between the heating mat and the growkit. (1 cm) 
  • Don't use a heating mat for temperatures above the 20 degrees. 
  • Try to avoid mushroom spores on the substrate, it will kill the mycelium.
McKennaii XL Mycelium box (2100ML)

(Cristian )
Very fast and reliable sendings. Until now i was very satisfied . I have already wrote two mails to the support and did not got a answer back . I bought the XL McKanni Mushroom kit , and it had just Aborts and a bad quality over all . I have bought a B+ Kit that was much more effective so this ain’t my mistake that it won’t work.
I am disappointed that the support did not even answer my messages. So 1 star from my side .

Evaluation: [out of 5 Stars]

(Michal Ondrusek)
I'm disappointed with the effect. mckennaii should be the strongest, but I enjoyed 8 g and the effect was mild so I took another 4 g of dried mushrooms to make the effect of slag better. 12 g is enough for a medium effect. so those mushrooms are weak. I used to take 7 g Mckennaii and flew in space now I use 12 g and I have mild states and mild visualizations. I'm sorry, but it's not strength anymore
Evaluation: [out of 5 Stars]

Thanks Avalon! Great first flush!! Waiting for the test ;) *****
Evaluation: [out of 5 Stars]

(Anonymous )
Fast and discrete leve the product, love avalon
Evaluation: [out of 5 Stars]

Excellent growkit! Two great flushes, very meaty mushrooms, amazing visionary guides.
Evaluation: [out of 5 Stars]

(Piotr Affeltowicz)
Fast shipping, good service and prices. Love avalon!
Evaluation: [out of 5 Stars]

Strongest of the strains available by my experience.
Evaluation: [out of 5 Stars]

Also ich bin echt überrascht wie viele Pilze da raus kommen über 70-80 Stück sind sicher der erste flush.. und die Lieferung war schnell und diskret.. meine Favorit Seite an jetzt!! Danke Avalon!
Evaluation: [out of 5 Stars]

(Mathieu Calmettes)
0 problème de livraison, rapide, efficace, comme je les aimes tout simplement ðŸâ€˜
Evaluation: [out of 5 Stars]

Nice Flash, big Flushes! If you take more (4 to 5 gram) the trip is a little bit like a small dmt-trip! Thanks Terence Mc Kennaii however you die Thatcher :-)
Evaluation: [out of 5 Stars]