An all-in-one bag holds a layer of sterilised, nutrient-enhanced grain at the bottom and a bed of sterilised CVA substrate on top, inside a filter-patch bag with a self-healing injection port. The whole grow happens inside that bag until the last step. These are the instructions we send with ours, with more detail than fits on the card.

What you need

• The all-in-one bag.
• A liquid culture syringe of a gourmet species. Oysters are the ideal match for a coir-based all-in-one.
• 70% isopropyl alcohol and a lighter or torch.
• A dark cupboard or box at 20 to 26°C.
• Later: a spray bottle, and somewhere with indirect light.

Stage 1: inoculate (day 0)

1. Clean

   Wipe the table, your hands and the outside of the bag with alcohol. Shake the syringe to break up the mycelium.

2. Flame

   Fit the needle, flame the tip until it glows, let it cool for ten seconds.

3. Wipe the port

   Alcohol on the port, firm pressure, let it flash off.

4. Inject into the grain

   Keep the bag upright. Push the needle through the port, angle it down into the grain layer and inject 2 to 5 ml for a 1kg bag, 4 to 8 ml for 2kg. Two or three spots are better than one.

5. Store

   Label with the species and date. Stand it upright in the dark at 20 to 26°C with the filter patch uncovered.

Stage 2: the grain colonises (days 3 to 21)

Nothing happens for a few days. Then white fuzz appears at the injection points and spreads across the grain. Oysters usually have the grain layer mostly white in 7 to 14 days; lion's mane and other slower species take two to four weeks. Do not squeeze, open or move the bag much during this stage.

Stage 3: mix (when the grain is mostly white)

This is the step that replaces spawning to a tub. With the bag still sealed, massage the grain layer so the kernels separate, then work the colonised grain up into the substrate layer and knead until it is spread evenly through the whole bag. Take your time; thorough mixing now means an even, fast run. Flatten the bag into a brick, press out loose air, and put it back in the dark.

Stage 4: the substrate colonises (one to three weeks)

The mixed bag goes from speckled to white. Oysters in a coir mix are usually fully colonised in 7 to 14 days. When the whole block is white, give it another three to five days to consolidate: the mycelium builds strength in that time and pins better for it.

Stage 5: fruit

1. Open

   Either cut the top of the bag off above the block, or cut a 5cm X in one face. Opening the top gives a bigger first flush; a cut gives a tidier cluster. Oysters are happy either way.

2. Humidity

   Mist the inside of the bag walls, not the block, two or three times a day, or stand the bag in a clear tub with a loose lid. You want the air at 85 to 95% humidity.

3. Fresh air

   Oysters need a lot. If stems grow long and caps stay small, give it more air: open the tub more, fan it, move it somewhere with gentle airflow.

4. Light

   Indirect daylight or a cheap LED 12 hours a day. Light tells the block which way is up; it does not feed it.

5. Harvest

   Pins appear in 3 to 7 days and double daily. Harvest oysters when the cap edges flatten and before they curl up, by twisting the whole cluster off at the base. Harvest guide.

Second flush

After the first harvest, pick off any leftover stubs, let the block rest in fruiting conditions for a week, and if it feels light, soak it in cold water for four to eight hours, drain and return it to the chamber. A second flush follows in one to two weeks. A third is possible if the block is still white and firm.

What can go wrong

• Nothing after two weeks. Too cold, or a weak culture. Move it somewhere warmer; if still nothing at three weeks, see grain bag not colonising.
• Green, black or pink patches. Contamination. A sealed bag with mould goes in the outside bin, sealed. Contamination guide.
• Long stems, tiny caps. Not enough fresh air during fruiting.
• Dry, cracked pins. Not enough humidity. Mist more, or add a tub.

Written by the Aus Myco Kingdom crew. Everything here is general growing information for gourmet and medicinal species; your room, your climate and your culture will have the final say.