Cultivation guides
How a grow goes, stage by stage
Six stages from a sterile jar to the next flush, with the numbers that matter at each one: temperatures, humidity, days, ratios. Plus the topics that cut across them and a field guide for when something looks wrong.
The grow, in order
Inoculation and colonization
Getting spores or culture into sterile grain or PF Tek jars, then waiting out a clean, even colonization.
You're here if: You have sterilized jars or bags that have cooled to room temperature and nothing has gone in yet.
Takes 2–4 weeks
Spawn to bulk
Mixing colonized grain into pasteurized bulk substrate, then letting the tub colonize sealed and undisturbed.
You're here if: Your grain spawn is fully white, with no bare kernels and a clean, mushroomy smell.
Takes 1–3 weeks
Pinning
Switching to fruiting conditions so the surface forms knots and pins: fresh air, light, and a surface that stays dewy.
You're here if: The substrate or cake is fully colonized and has had a few days to consolidate.
Takes 5–14 days
Fruiting
Carrying pins through to mature mushrooms: more fresh air, steady humidity, dry caps, and watching for problems.
You're here if: Pins are pea-sized or bigger and clearly growing each day.
Takes 4–8 days
Harvest timing
Picking each fruit as its veil stretches and tears, before the cap flattens and drops spores.
You're here if: Caps have stopped being round and closed and are starting to open.
Takes Hours per fruit
Next flush
Cleaning up, checking for contamination, putting water back with a dunk or misting, and waiting for the next wave.
You're here if: The flush is fully picked and the surface is bare.
Takes 7–14 days
Something looks wrong?
- Contamination IDTelling trich, cobweb, bacteria and other moulds apart from bruising, metabolites and hyphal knots, and what to do about each.
- TroubleshootingNo pins, overlay, aborts, side pins, wet spots and stalled colonization: likely causes and fixes, climate first.
Green, pink, orange or black powder, or a sour smell: go straight to contamination ID.
Across every stage
- Containers: PF Tek, AIO bags and monotubsThe three common setups compared, plus how to build a shotgun fruiting chamber and a simple monotub.
- Substrates and casingBulk substrate recipes as ratios, getting to field capacity, pasteurizing, and when a casing layer helps.
- Climate control: fresh air, humidity and lightHow fresh air, humidity, temperature and light trade off against each other, and how to read the mushrooms instead of a sensor.
- Clean work, agar and liquid cultureThe habits that keep jars clean: a still air box, flame and bleach, and how agar and liquid culture fit in.
Glossary
42 terms. Dotted words across the guides open these definitions.
- Abortsaborted pins
- Pins that stop growing while their neighbours keep going; their caps darken to brown or black within a day or two. Troubleshooting
- Agar
- A firm gel in a petri dish that mycelium grows across, used to check a culture is clean and to pick strong, fast sectors before they go to grain. Clean work, agar and liquid culture
- AIO bagall-in-one bag
- A filter-patch bag that already holds sterilized grain and substrate, so you inject, colonize and fruit without ever opening it to mix. Containers: PF Tek, AIO bags and monotubs
- Bacterial blotch
- Yellow-to-brown, slightly sunken spots on caps, caused by bacteria that thrive when caps stay wet for hours. Contamination ID
- Birthing
- Sliding a fully colonized PF Tek cake out of its jar so it can be fruited in a chamber. Inoculation and colonization
- Bulk substratebulk
- The large, low-nutrient bed (usually coir-based) that colonized grain is mixed into so it can grow out and fruit. Substrates and casing
- Casing layercasing
- A thin, water-holding top layer with no food in it, spread over colonized substrate to keep the fruiting surface evenly moist. Substrates and casing
- Cobweb mouldcobweb
- A grey, see-through, wispy mould that stands up off the surface and can spread an inch or more in a day. Contamination ID
- Colonization
- The stretch where mycelium grows through grain or substrate until every part is white and knitted together. Inoculation and colonization
- Consolidation
- The few days after a surface first looks white, when mycelium keeps thickening inside the substrate before fruiting conditions start. Spawn to bulk
- CVGcoir, vermiculite, gypsum
- A common bulk substrate of coconut coir, vermiculite and a little gypsum, hydrated with hot water. Substrates and casing
- Dunksoak, rehydrate
- Soaking a picked cake or bulk bed in clean cool water for a few hours to replace the water the last flush took out. Next flush
- FAEfresh air exchange
- Fresh air exchange: swapping the stale, carbon-dioxide-rich air in a container for room air. Climate control: fresh air, humidity and light
- Field capacity
- Holding as much water as a substrate can without dripping; squeezed hard, it gives a few drops, not a stream. Substrates and casing
- Flush
- One wave of mushrooms that come up together; a healthy bed gives several, each usually smaller than the last. Next flush
- Fruiting conditions
- The switch from sealed, dark colonization to fresh air, light and high surface humidity that tells mycelium to make mushrooms. Pinning
- Fuzzy feet
- Bright white fuzz climbing the base of stems, a sign of too much carbon dioxide or not enough fresh air. Climate control: fresh air, humidity and light
- Grain spawnspawn jar
- Sterilized grain, such as rye or millet, fully colonized by mycelium and ready to inoculate bulk substrate. Inoculation and colonization
- Hyphal knots
- Tiny dense white specks on the surface, the very first step toward pins. Pinning
- Inoculation
- Introducing spores or living culture into a sterile jar, bag or plate. Inoculation and colonization
- LCliquid culture
- Liquid culture: a sterilized sugar-water broth with living mycelium suspended in it, injected like a spore syringe but faster to take. Clean work, agar and liquid culture
- Lipstick mould
- A mould that starts as a white film or small balls and turns pink to red as it ripens. Contamination ID
- Metabolites
- Clear to amber droplets that bead on healthy mycelium under stress; harmless in small amounts. Contamination ID
- Monotub
- A single plastic tub, drilled or fitted with filtered holes, used both to colonize bulk substrate and to fruit it. Containers: PF Tek, AIO bags and monotubs
- Mycelial bruisingbruising
- Blue or blue-green staining inside mycelium or mushroom flesh where it was touched or damaged; it sits in the tissue and never wipes off as powder. Contamination ID
- Overlay
- A flat, leathery white mat that keeps thickening across the surface instead of forming pins. Troubleshooting
- Pasteurization
- Holding substrate hot, around 160–180 °F (71–82 °C) for an hour or more, to knock back competitors without sterilizing it. Substrates and casing
- PF Tek
- A beginner method that colonizes small jars of brown rice flour and vermiculite, then fruits the cakes in a humid chamber. Containers: PF Tek, AIO bags and monotubs
- Pinspinheads, pinning
- Baby mushrooms a few millimetres tall, the first visible stage after hyphal knots. Pinning
- Primordia
- The formal name for pins: the earliest mushroom bodies, before cap and stem are clearly separate. Pinning
- RHrelative humidity
- Relative humidity: how much water vapour the air holds compared with the most it could hold at that temperature. Climate control: fresh air, humidity and light
- Rhizomorphic
- Mycelium that grows in branching, rope-like strands, as opposed to even, cottony growth. Inoculation and colonization
- Shotgun fruiting chamberSFC
- A clear tub drilled all over with small holes and floored with wet perlite, used to fruit PF Tek cakes. Containers: PF Tek, AIO bags and monotubs
- Side pins
- Pins that form against the container wall, down the sides of the substrate, instead of on top. Troubleshooting
- Spawn
- Any colonized material used to seed something bigger, most often grain spawn mixed into bulk substrate. Spawn to bulk
- Spawn ratio
- How much colonized spawn goes in compared with bulk substrate, by volume, written spawn to bulk, such as 1:3. Spawn to bulk
- Sterilization
- Killing everything living in grain or substrate with steam at 15 psi (250 °F) in a pressure cooker: about 20 minutes for small PF jars, hours for big grain loads. Clean work, agar and liquid culture
- Still air boxSAB
- A clear tub with arm holes that stops air currents while you open sterile jars, plates or bags. Clean work, agar and liquid culture
- Tomentose
- Even, cottony mycelium without strands; normal for many cultures and not a sign of contamination. Inoculation and colonization
- TrichTrichoderma, green mould
- Trichoderma, the common green mould: a dense white patch that turns forest green from the centre as it releases spores. Contamination ID
- veil breakpartial veil
- The moment the thin tissue joining the cap edge to the stem tears, exposing the gills; the usual harvest cue for cubensis. Harvest timing
- Wet spotsour rot
- A bacterial infection of grain that leaves kernels looking wet and slimy, stalls colonization and smells sour. Contamination ID
Recommended reading
- The Psilocybin Mushroom Bible, Virginia Haze and Dr. K. Mandrake, 2016. Step-by-step PF Tek, grain, bulk, agar and contamination chapters with photos.
- The Mushroom Cultivator, Paul Stamets and J. S. Chilton, 1983. The classic reference for growth parameters, pinning biology and disease.
Guides cite their sources at the bottom of each page. Seen something that doesn't match? Add your grow report.