How to Grow Mushrooms at Home: 4 Stages, 3 Routes

To grow mushrooms at home you add spawn (living mycelium on grain or sawdust) to a prepared substrate, wait while it colonizes, then give it the right conditions to fruit. The easiest starting points in our sources are a ready-made kit, a bucket or bag of pasteurized straw for oyster mushrooms, and hardwood logs for shiitake. Logs are easy to run but slow. This guide covers the four stages, the three routes and where each one can go wrong. Every number comes from an extension source, and where two sources disagree we show both. This site covers gourmet and medicinal species grown for cultivation only, and does not cover wild identification or foraging.

The four stages

Mushroom growing is not like gardening, because you are growing a fungus, not a plant. Cornell lays out seven stages of cultivation, and for home growing they reduce to four.

1. Spawn. Spawn is mycelium growing on a carrier. Cornell lists three common forms: grain, sawdust and plug. Our mushroom spawn guide covers what each is for.
2. Substrate. This is the food the mycelium runs through, such as straw, hardwood sawdust or a log. It usually has to be heat-treated or otherwise cleaned first. See mushroom substrate.
3. Colonization. The mycelium spreads through the substrate, usually in the dark. For oyster mushrooms on straw UF gives a spawn run of 2 to 3 weeks. For shiitake on logs Cornell gives 6 to 18 months.
4. Fruiting. Mushrooms form when conditions change. UF says oyster fruiting is triggered by light plus a lower temperature, with good air exchange so carbon dioxide does not build up.

The first three stages are a race between your fungus and everything else that wants the substrate. That is why contamination and clean technique come up in every route.

Three beginner routes

The difficulty column is our reading. None of the sources ranks routes.

A kit. UF describes the kit route as setting up a ready-made, already colonized kit in a suitable fruiting environment. Our mushroom grow kit guide covers setting one up, flushes and what goes wrong.

A straw bucket or bag. UF lists three components for oyster cultivation: healthy spawn, pasteurized substrate and a container. Wisconsin’s home bucket method packs wood chips and grain spawn into a 5-gallon bucket and holds it at about 65 to 75°F, away from sunlight, undisturbed for about 14 days. Once pins start, you remove the bag and mist the outside of the bucket to hold humidity.

Logs. You drill rows of holes in fresh hardwood, insert sawdust or plug spawn, and seal each hole with food-grade wax. After that the work is waiting and then soaking. See growing mushrooms on logs.

Which species suit beginners

Our sources point two ways, and we flag this as our reading.

• Oyster. Wheat straw is the standard substrate (UF). Cornell says straw can be inoculated outdoors with little contamination concern, and that fruiting is best done indoors. Our oyster mushroom page has the full stage-by-stage numbers.
• Shiitake. Cornell groups strains into Wide Range (WR), Warm Weather (WW) and Cold-Weather (CW), and calls Wide Range the easiest for beginners. Cold-weather strains need a longer spawn run. Our shiitake page has the detail.
• Lion’s mane. Cornell says lion’s mane, like shiitake, does best on sawdust, and that indoor or controlled-environment production is common. Our sources give no beginner rating.

We have no sourced beginner guidance for other species yet, so we do not rank them.

Conditions at a glance

The two species most beginners start with want very different things. This table uses only figures from our fact sheets, and a dash means our sources do not state it.

Sources differ on oyster details. UF puts the spawn run at 24 to 25°C (75 to 77°F), while Cornell says to keep incubation near 70°F and not above 80°F. For fruiting humidity UF gives about 90% and Cornell’s fruiting room held 85%. Both are fine as a range to work within.

How long each route takes

Timing is where the routes differ most. Oyster on straw is the fastest of the three that start from scratch: Cornell gives about five weeks from inoculation to harvest, and UF says pinning begins about three weeks after dark incubation starts. Shiitake on logs is slow because the mycelium has to colonize solid wood, with 6 to 18 months of incubation (Cornell). Once logs are running, Cornell says they fruit twice a year for three to four years, so the slow start buys a long harvest. Kits skip the colonization wait entirely, but our sources give no timeline for a particular kit, so follow its own instructions.

Where beginners go wrong

• Skipping heat treatment on straw. UF pasteurizes straw at 165°F (74°C) in a water bath for 1 to 2 hours. See mushroom substrate for where Cornell’s advice differs.
• Ignoring spots. UF says blue, green, black or yellow spots mean contamination, and that heavily contaminated bags are best discarded.
• Fruiting without fresh air. UF stresses air exchange in the fruiting chamber so CO2 does not build up while humidity stays high.
• Waiting too long to inoculate logs. Cornell says not to wait longer than three weeks after felling, because the log is more likely to be infested with competing fungi or dry out.
• Rushing the first soak on logs. Cornell says growers who waited longer before the first soak got significantly more shiitake. Patience pays on this route.
• Treating one number as universal. The 5 to 10% spawn rate you may see, for example, is UF’s figure for oyster on straw, not a rule for every species. See the spawn guide.

Guides to read next

• Mushroom grow kits: setting one up, flushes and what can go wrong.
• Mushroom spawn: grain, sawdust and plug spawn, and spawn rates.
• Mushroom substrate: straw, sawdust, pasteurizing and sterilizing.
• Growing mushrooms on logs: the slow, low-effort route.
• Mushroom contamination: signs, causes and clean technique.

Where to start

If you want mushrooms soonest and want the least risk, start with a kit. If you want to understand the whole cycle, try a bucket of straw with oyster spawn. If you have hardwood and patience, logs will keep producing for years: Cornell says shiitake logs fruit twice a year for three to four years, and Maryland says about three to five.