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Home / Mushroom Cultivation / Mushroom Grow Kits / Rye Grain MycBox Grow Kit
Rye Grain MycBox Grow Kit
Sterilised at 15 PSI in an electric autoclave, then processed and bagged under clean ISO4 filtered air-flow - before being heat-sealed shut.
Coffee-enhanced and ready to rock and roll.
Your favourite mushrooms will deliver 3+ harvests until the substrate is completely spent of nutrients.
This old classic makes a surprise return in 2026. Also, we're giving away 200g of dry coco coir substrate with this kit incase you want to go crazy and try a 33% monotub style grow. otherwise put it in a drawer for your next grow (you don't need it).
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Some formats are out of stock
Want to know the moment it returns?
Rye Grain MycBoxΒ with 1 injection
Inoculation
- Remove the MycBox from it's bag - it's already clean enough to inject but if you want, wipe the grey rubber port with the green Clinnel wipe
- Wait a few seconds for it to dry, then inject 2-3ml of gourmet syringe solution
- Place the MycBox somewhere warm to fully colonise (23C is common for many species, give or take a couple of degrees)
- Follow the rest of the guide until harvest
The white HEPA filters on the lids will filter dust and mould spores and allow clean air exchange. Don't try to remove these!
NEVER open the MycBox before full colonisation of mycelium or the kit will be ruined with contamination.
Click the 'Instructions' tab above to read our detailed guide
What's Included
- 1200ml MycBox of Coffee-enhanced Organic Rye Grain Substrate and Gypsum (18x12x7cm)
- HEPA-Filtered and Inject-Thruβ’ lid system for ultimate contamination resistance
- Humidity Tent to fruit your mushrooms inside
- Hygiene Kit includes 70% IPA wipe, needle, alcohol wipe and hand wipe
- 2L Perlite to maintain the perfect humidity level throughout the mushroom fruiting process
- Bonus: Includes a bag of coir so you can optionally try MonoTub-style grows (you just add water and microwave)
Not included
- Gourmet Spore or Culture Syringe
Storage
If you cannot use your grow kit right away, we would advise that you store it in a (clean) fridge for a maximum of 2 weeks inside its clean bag.
If you can't store it in a fridge, don't leave it for any longer than 1 week.
The longer you leave it, the more moisture will be lost from the substrate and if too much moisture is lost, colonisation will just not happen.
Always inoculate your grow kits as soon as you possibly can!
Advice
- This grow kit is tailored for all experience levels
- Can take anywhere from 5 to 8 weeks to fully colonise at optimum temperatures
- Does not come supplied with a gourmet spore or culture syringe.
- Some wood-loving species like Shiitake may not fruit on this substrate.
Replacement cover, explained
EZ-Replacement
Covered on this product
- No Gloves
- S
- M
- L
- XL
This product is covered if something goes wrong, so we can make sure you get another kit to try again with. The last thing we want is customers abandoning this hobby because of a mistake. So, if something goes wrong within 12 weeks of us dispatching it to you then follow the steps below to get a new kit on the way.
How a claim works
- Open the replacement portal from your logged in account.
- Pick the order and the item. If more than one is affected, say how many.
- The replacement lands in your basket at £0.
- Check out and pay the postage. That is the only thing you pay.
No photos, no explanation, nobody to convince.
We built this shop to be human. When you need a replacement, take it.
Q & A
Rye Grain MycBox Grow Kit
For cultivating legal gourmet mushroom species only.Sold as a sterile substrate kit for home cultivation. We trust you to be responsible.
0-3 working day dispatch or a free gift if we are late (UK-only pledge). Order and pay before 1pm Monday to Friday.
If your parcel does not arrive
Contact us, not Royal Mail. Royal Mail only deal with the sender, which is us:
“If you're the recipient please contact the sender. They will contact us to make enquiries on your behalf.”
Royal Mail: what to do if your item doesn't arrive
When Royal Mail treat an item as missing
Royal Mail will not look at a claim until this much time has passed after the date your item was due. They also say early claims cannot be processed.
- Tracked 24 and Tracked 48: due date plus 7 working days
- Standard and Tracked to Europe: due date plus 20 working days
- Tracked outside Europe: due date plus 25 working days
- Standard outside Europe: due date plus 25 working days
What Royal Mail pay for a lost item
- International Standard and International Economy: the lower of market value or £20
- International Tracked: the lower of market value or £50
Royal Mail: international compensation
That is what Royal Mail pay us. What you get from us is covered by our replacements policy, which does not depend on Royal Mail paying out.
Stopped at customs
In the 9 years we have been running, we have only had a couple of issues with parcels being stopped at customs - if this is the fault of us (USA seized a parcel once because we put a Cadbury's chocolate bar into a parcel as a treat ) then of course we will sort it out and take the hit. But if it's not our fault, then we will not cover any replacement cost. Luckily, this situation has probably happened a few times in all of these years.
Full shipping and dispatch details, including every international price