XL and XXL MonoBag™ Grow Kit

1. Inoculation of SpawnBags

Reducing the risk of contamination is crucial in successful mushroom cultivation, and you can achieve this by working in a small, clean, and draft-free space, ideally using a Still-Air Box (SAB).

Before starting, cleanliness is key. Shower, clean clothes. Your hygiene kit contains a face mask and wipes for cleaning your hands and forearms.

Next, prepare your syringe by attaching a sterile needle. Or if you're using a spore swab then have that to hand. Now, get your SpawnBags ready by using the green Clinell alcohol wipe to sanitise all around the white inocuport area. Now peel this inocuport back just enough that you can see the entry site... swiftly inject your 3ml of spore or LC solution. If you have a spore swab, push it in and move it around to dislodge spores onto the grain. Once you're done, restick the inocuport (making sure its tightly adhered with no creases please!)

While injecting or swabbing, try to direct towards the edge of the SpawnBag (it will let you see the mycelium faster than going into the centre of the grain).

2. Colonisation of SpawnBags™

After inoculating your SpawnBags, it's time for colonisation. Just sit them on a shelf and forget about them for a couple of weeks. Make sure the direct sunlight is hitting them.

3. Preparing Your Substrate

XXL MonoBag Grow Kit (with pre-sterile steriCVG™ Substrate)

If you chose the XXL MonoBag Grow Kit, it means you'll need to email us when you need the substrate sent. We'll have it to you within a couple of days. Once you have this, move to the next stage.

XL MonoBag Grow Kit (with diyCVG™ Substrate)

When the grain inside your SpawnBag is fully covered with healthy, white mycelium, you're ready to prepare your substrate. It's important not to open your SpawnBag before full colonisation to prevent uncolonised grains colonising with mold.

Pour the bag of dry coir, vermiculite and gypsum into a kitchen pot. Now add in 1100ml of tap water and give it all a good stir around. Put a lid on the pot.

With kitchen scales, you should note down the weight of the lidded pot and substrate - it will be handy for knowing how much water is lost from steam evaporation.

Now put on medium heat, and every once in a while weigh the pot. Once it has lost 300g of water (which is same as 300ml of water), leave it with the lid on to cool down to room temp and it's done.

This will produce a final substrate weight of 1000g which will be approximately 2L in volume.

4. Spawning to Substrate

Before proceeding, clean your hands and forearms and wipe clean your SpawnBags. Now pour your substrate into your XL or XXL MonoBag™.

Open your SpawnBag and empty the mycelium-covered grain out into your MonoBag. Squeeze through the bag or put your clean hands inside to break apart the grain until it separates into individual grains, mixing it all up into the substrate as evenly as you can. This will speed up the colonisation process, and the faster that goes, the less likely contamination becomes.

Because we are dealing with living mycelium now and not spores, the ideal colonisation temperature is between 24-26°C. Getting the temperature as ideal as possible at this point is crucial for success. You need the colonisation of the substrate to be quick, or there's a higher risk of unwanted microbes taking hold.

In the right conditions, it should take around 7-10 days to see full colonisation of the substrate. Only when you're confident that the substrate is fully colonised with strong, healthy mushroom mycelium are you ready to begin fruiting.

5. The best bit... Fruiting your mushrooms!

Maintaining a slightly cooler (but still warm) temperature of 20-22°C during the fruiting stage is essential for excellent results with many popular species of mushrooms.

Humidity and Air Exchange

Humidity and FAE (fresh air exchange) are extremely important for pinning and healthy mushroom development, as is temperature and light. They all need to work in harmony. Humidity will naturally build up inside the grow tent from water you previously added to the substrate mix, which is still stored in the cake. Unlike some other grow kits, you should not mist this kit (unless it looks dry).

The only time you'll open your tent is when you're ready to harvest your mushrooms. Even peeking for a few seconds is enough to lose a lot of humidity and cause growth defects such as aborted pins and caps breaking. We suggest cutting a 1cm slit through both sides of the tent near the top and placing an electric fan somewhere in the room on a low setting. This will create a gentle air current inside the room, which will help increase the FAE inside the grow tent.

Light and Environmental Conditions

Your mushrooms will need light to grow. We recommend indirect sunlight or a 6-7000K LED or fluorescent light a few feet away - if the light is heating the substrate, move it further away. If you notice the inside of your grow tent looking dry, it may be due to the fan being too close, the holes you cut being too big, or grow lights (if using them) being too close and hot. Observe what's happening and adjust your setup as required. Fantastic results depend on it.

Pinning and Growth

After around 3-7 days, you'll hopefully begin to see lots of tiny white dots. These are hyphal knots that will develop into primordia, aka mushroom pins. It will take 4-5 days for them to grow into fully mature mushrooms ready for harvest. During this time, they'll let you know if something isn't quite right. Fuzzy mycelium at the base of the mushrooms and/or thin stems are an indication that more FAE is needed. Increasing the fan speed or length of the cuts on the bag might be something to try.

Don't worry about any mushrooms growing around the sides and bottom of the cake. You'll still be able to harvest them. If you want to give your mushrooms more room to grow next time, use a fruiting chamber instead of a grow tent.

Harvesting and Subsequent Flushes

When the veil beneath one of your mushroom caps is about to tear off, this is when you should harvest your first flush. If you don't get there quickly enough, spores will begin to drop from your mushroom caps and make a mess! It's best to cut the mushrooms off with a clean scalpel or knife. You can also just pull them off, but be careful not to damage the substrate too much.

After you've harvested all the mushrooms from your first flush, you can use a method called "dunking" to get more moisture into your substrate. Simply fill a container with water deep enough to submerge your cake and place it in the water. It will float to the top, so you need to use something to weigh it down. You need it to be fully submerged in water at all times.

Place a lid on the container or cover it to keep everything clean. Leave your cake submerged for anything between 6-24 hours, depending on how much patience you have. But obviously, the longer you leave it, the better your results will be. When you remove the cake from the water, give it a rinse under the tap and allow excess water to drain away before placing back into your grow tent.

You should continue to dunk your substrate after each flush. If you've taken good care of it, you should achieve multiple flushes of mushrooms from your grow kit before the nutrients are all used up.

If there's anything you're still unsure about and you need some advice on growing your gourmet mushrooms - get in touch!

Happy shroomin' ???

Last updated on 03 June, 2025