Q
Is it OK to store these and the multigrain at room temperature, around 19c, for a couple of weeks before usage, or is it important to store them at a colder temperature to reduce the risk of contamination?
A
Should be fine :)
Home / Mushroom Cultivation / Spawn & Substrates / Wholegrain SpawnTub™
Ready to inoculate
Spawn & Substrates
Wholegrain SpawnTub™
A sealed tub of sterilised wholegrain with a self-healing injection port. Inject your own legal gourmet culture, let it colonise, then break it up and use it to seed a bulk substrate.
★★★★★ 4.9 · 12 reviews Price range: £16.00 through £120.00
Choose your option
Made in small batches. Inoculate as soon as you can after delivery.
Sterilised in batch
Heat treated so the grain is clean and ready for your culture.
Heat treated so the grain is clean and ready for your culture.
Self-healing port
Inject without opening the tub, which keeps contaminants out.
Inject without opening the tub, which keeps contaminants out.
First stage spawn
Built to colonise fast, then expand into a much larger bulk grow.
Built to colonise fast, then expand into a much larger bulk grow.
StageFirst stage grain spawn
State on arrivalSterilised and sealed, ready to inoculate
Inoculate withLiquid culture or spore solution (not included)
Typical inoculation doseAround 1 to 5ml per tub
Colonisation temperatureAround 21 to 24C for most gourmet species
Colonisation timeAround 2 to 3 weeks
Spawn to bulk ratioAbout 1:2 to 1:5
The short version
The Wholegrain SpawnTub is a sealed tub of cooked, sterilised grain that is ready for you to inoculate. You inject a legal gourmet culture or spore solution through the port in the lid, let the mycelium take over the grain, then use that colonised grain to seed a larger bulk grow.
It removes the hardest and messiest part of making spawn at home, which is cooking and pressure sterilising grain without it spoiling. The tub arrives done and sealed, so you go straight to inoculation.
What it is
Sterilised grain, sealed and ready
Grain spawn is the first stage of most indoor mushroom grows. Mycelium is grown through nutritious grain first, and that colonised grain then becomes the seed for a much larger batch of bulk substrate. The grain gives the mycelium plenty of food and many starting points to spread from.
This tub holds whole grain that has been cooked to the right moisture and then sterilised, so it is clean and ready to receive your culture. The lid has a self-healing injection port. You inoculate through that port with a needle, so the tub never has to be opened until the grain is fully colonised. Less opening means less chance of contamination.
Grains such as rye and wheat are used for spawn because they hold water and feed the mycelium well. Rye holds more water than most grains and feeds the mycelium well, which is why it is the standard spawn grain.
How to use it
From sealed tub to a colonised block
1
Set up clean
Work in a still room with the doors and windows shut. Wipe your surface, your hands, the tub lid and the syringe with 70 percent isopropyl alcohol before you start.
2
Inject your culture
Push the needle through the self-healing port and dispense your liquid culture or spore solution, around 1 to 5ml per tub. Change the angle as you go so it lands in several spots across the grain. More starting points means faster, more even colonisation. More liquid is not better, as too much adds moisture the grain does not need. Then leave the tub sealed.
3
Colonise
Keep the tub somewhere warm, dark and undisturbed. Most gourmet species sit around 21 to 24C. Full colonisation usually takes around two to three weeks, depending on the species, the grain and the temperature.
4
Shake to spread
Once growth is roughly a third of the way through, shake the tub to break the grain apart. This spreads the mycelium and speeds up the rest of the colonisation. Do not shake earlier than this, as it can damage young mycelium and set the grow back.
5
Spawn to bulk
When the grain is fully white, break it up and mix it into a prepared bulk substrate such as coir or a manure based mix. A common ratio is about one part spawn to two to five parts bulk, using more spawn the less sterile your setup is.
Storage and good practice
Keep it cool and use it whole
If you cannot inoculate straight away, keep the sealed tub somewhere cool, dry and out of direct light. Sterilised grain kept at room temperature is best used within about a month. The fridge extends this to a few months. The longer it waits, the more chance there is of a stray contaminant taking hold, so inoculate as soon as you reasonably can.
Once you open a tub, use all of it. Part used grain left sitting is a common source of contamination. Inspect before you inoculate and again after colonising. Healthy spawn is bright white. Any green, black, grey or pink growth, or a sour or off smell, means that tub is contaminated and should be discarded. Do not open a contaminated tub indoors, as that releases spores into the room. Seal it and remove it first.
What it is not
Not a finished kit, and not pre seeded
This tub is grain only. It does not come with a culture and it will not grow anything on its own. You supply the legal gourmet culture or spore solution. It is also not a fruiting substrate by itself. It is the spawn you use to seed a larger bulk grow.
Common questions
Frequently asked
No. The tub is sterilised grain only. You inject your own legal gourmet culture or spore solution through the port.
Wipe the port and your syringe with isopropyl, push the needle through the self-healing port and dispense around 1 to 5ml, angling it so it lands in several spots. More liquid is not better, as too much adds moisture the grain does not need. Then leave it sealed.
Usually around two to three weeks to fully colonise, depending on species, grain and temperature.
When growth is about a third of the way through. Shaking spreads the mycelium and speeds things up. Shaking earlier can damage young mycelium, so wait.
As a guide, mix one part colonised grain to roughly two to five parts bulk substrate, using more spawn if your setup is less clean.
Keep the sealed tub cool, dry and out of light. Use within about a month at room temperature, or refrigerate to extend it. If you see any colour other than white, or it smells off, do not use it.
What customers say
Reviews
★★★★★ 4.9 from 12 reviews ✓ All from verified purchases
★★★★★✓ VerifiedOrdered 27 May 2021 · Reviewed 2 Jul 2021
These SpawnTubs have been a great way for a novice like me to get started. Sterilized and ready to use, I keep ordering these because they’re a reliable way to get my mycelium started, especially when using the agar method first. Highly recommended.
0
★★★★★✓ VerifiedOrdered 19 May 2021 · Reviewed 2 Jul 2021
Rye grain tubs are excellent quality.
0
★★★★★✓ VerifiedOrdered 23 Nov 2021 · Reviewed 2 Dec 2021
Excellent quality product, personal service, fast order turnaround and communication. Love it!
0
★★★★★✓ VerifiedOrdered 30 Sep 2021 · Reviewed 12 Oct 2021
Great 🔬
0
★★★★★✓ VerifiedOrdered 14 Aug 2021 · Reviewed 30 Aug 2021
Nice concept, makes it's super easy for a beginner like myself!
0
★★★★★✓ VerifiedOrdered 25 Aug 2021 · Reviewed 3 Sep 2021
Bit pricey but it’s a good starter
0
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Ask the community
Questions and answers
Q
how long can i keep spawntubs in the incubator once they appear to be fully colonized? in other words, if i felt they needed a bit longer but wont be around to check, will they end up dying in the incubator?
A
You can get away with leaving them in the incubator for weeks, but if leaving them for extended periods of time you can place colonised SpawnTubs in the fridge. Only species I know this not to work with is Pink Oyster!
Q
Are these filled with your brand new MultiGrain spawn as supplied with MonoBox kits since 27th September? If not, are the Multigrain spawn tubs available to purchase as separate items?
A
This is now available in multigrain on a seperate product page :)
Q
Should this item be shaken at all at any stage of colonisation to promote a more homogenous mix? If so, could a recommendation be included please?
A
It can be shaken to help speed up complete colonisation at around 30% colonisation. Just do it the once though.
Q
Do I need to replace the filter film on the top before and after pressure cooking sterilisation? Or is it to be left?
A
Our SpawnTubs are already sterile, and ready to inject.
Do not tamper with the breathable HEPA filter strip, ever.
Q
What are the exact dimensions of the container. Including the inside lid circumference. And the grain fill level from inside of the pot.
A
Hi Joseph, sorry I don’t know. Not something we get asked every day tbh but when I get a chance I’ll look into it.
Q
What weight of grain is in the pot.?
Waiting for an answer.
Q
If these are left too long, is there a way to rehydrate them?
A
I wouldn’t recommend buying this product if you aren’t planning to use them till so far into the future that they dry out. It takes a verrry long time for grain to dry out.
Dry grain would only be good for the bin :)
Q
What are the dimensions?
Waiting for an answer.
Q
Will this need to be mixed with anything once colonisied? Or can i just put in fruiting conditions? Many thanks!
A
You could just introduce this to fruiting conditions, but this one is really designed as a spawn tub only (to mix with a substrate or more more spawn).
If you are looking to just introduce to fruiting conditions after colonisation then I’d recommend opting for the Rye Grain MycoTub Grow Kit as not only has it got a much higher fill level of grain but it has a vermiculite casing layer too and all the other bits and bobs you’ll want to have (perlite, GrowTent etc)
Sold for microscopy and the legal cultivation of gourmet and culinary mushrooms only. No spores or cultures are supplied with this product.
We work hard to keep this information accurate and to cite reputable sources, but the occasional mistake can still slip through. Always check the product label and a current reference before relying on any figure for something important.