What temperature do mushrooms grow best at?

It depends on the stage. Colonization (spawn run) is warm — most cultivated mushrooms colonize fastest at 20–25 °C in the dark. Fruiting is cooler and species-specific: warm growers like pink and yellow oyster fruit at 18–30 °C, while cool growers like blue oyster, king oyster, and shiitake fruit best at 10–18 °C.

Is one temperature enough for the whole grow?

Almost. You can colonize nearly any species at a steady 20–24 °C. The difference shows up at fruiting: some species need a cool-down to trigger and hold pins. A basement that sits around 18–20 °C suits most oyster, lion's mane, shiitake, and chestnut year-round; warm-fruiting pink and yellow oyster prefer a summer room.

What happens if mushrooms are too cold or too hot?

Too cold during colonization and the spawn run stalls, which invites contamination. Too hot during fruiting and pins abort, caps thin out, or the mushroom bolts with long stems and small caps. Every species has a fruiting window; staying inside it is what gives even flushes.

What is the best temperature for growing oyster mushrooms specifically?

Grey and white oyster colonize at 18–24 °C and fruit across a wide 13–24 °C. Blue oyster is a cool grower (fruit at 10–18 °C) and is well suited to Canadian basements and shoulder seasons. Pink and yellow oyster are warm growers that need 18–30 °C to fruit.

The ideal temperature for growing mushrooms (by species)

By the MushroomGuide.ca Editorial Team Jul 5, 2026 Grow

“What temperature do mushrooms grow at?” has two answers, because a mushroom grow has two stages with almost opposite needs. Colonization (the spawn run, when white mycelium eats through the substrate) wants steady warmth. Fruiting (when mushrooms actually form) is cooler and species-specific — and getting that second number right is the single biggest lever on your yield.

This is the temperature reference, species by species, written for Canadian home growers. For the full conditions chart — humidity, fresh-air exchange, spawn rate, and days to harvest alongside these temperatures — see the mushroom growing conditions chart.

The one rule to remember

Colonize warm and dark; fruit cooler and fresh.

Most cultivated mushrooms colonize fastest at 20–25 °C in the dark. Then, to fruit, most want a drop into cooler air with fresh oxygen, light, and high humidity. The size of that drop, and the target window, is what changes from species to species.

Temperature by species

Species	Colonization (spawn run)	Fruiting
Grey oyster (P. ostreatus)	18–24 °C	13–24 °C
Blue oyster (P. o. var. columbinus)	18–24 °C	10–18 °C
White oyster (P. ostreatus)	18–24 °C	13–22 °C
Pink oyster (P. djamor)	24–30 °C	18–30 °C
Yellow oyster (P. citrinopileatus)	24–30 °C	18–30 °C
King oyster (P. eryngii)	20–24 °C	15–18 °C
Lion’s mane (Hericium erinaceus)	21–24 °C	15–22 °C
Shiitake (Lentinula edodes)	21–24 °C	10–18 °C
Chestnut (Pholiota adiposa)	22–25 °C	15–22 °C

Fruiting figures are the air temperature that gives the best pinning and cap development. A few degrees outside the range won’t kill a grow, but it costs you evenness and yield.

Warm growers vs. cool growers

Reading the table, the species sort into two camps — and that’s the most useful way to plan a Canadian grow:

Cool growers — blue oyster, king oyster, shiitake (fruit at 10–18 °C). These love a Canadian basement, a garage in spring and fall, or the shoulder seasons. The cool-down is often what triggers them to pin.
Warm growers — pink oyster, yellow oyster (fruit at 18–30 °C). These are summer mushrooms here. They pin fast and colonize hot, but they’ll sulk in a cold basement. Grow them when the house is warm.
In-betweeners — grey/white oyster, lion’s mane, chestnut (roughly 13–24 °C). The forgiving ones; a room that sits around 18–20 °C keeps them happy most of the year.

Colonization: why warm and steady matters

During the spawn run, you want the mycelium to outrun any competing mould. Warmth (20–24 °C for most species) keeps colonization fast; a cold room slows it down and hands contaminants an opening. Keep colonizing substrate somewhere dark and stable — a closet, a cupboard, a grow-tent corner away from drafts. Big temperature swings are worse than a steady temperature that’s a degree or two off.

Pink and yellow oyster are the exceptions that like it genuinely hot to colonize (24–30 °C) — near a warm appliance or in a heated tent in winter.

Fruiting: the cool-down and the window

Once a block is fully colonized, fruiting temperature does two jobs:

Triggering. For cool growers especially, dropping the temperature is part of the signal to start pinning. Moving a colonized blue-oyster or shiitake block from a 22 °C run into a 14–16 °C fruiting spot often kicks off pins within days.
Holding. Once pins form, staying in the window keeps caps thick and clusters even. Too warm and you get long stems, thin caps, and fast-but-poor flushes; too cold and growth crawls.

Hitting the numbers in a Canadian home

You rarely need special equipment — you need the right room for the season:

Basement (year-round ~15–20 °C): ideal for the cool and in-between growers. This is the workhorse space for most Canadian growers.
Garage (spring/fall): great for cool growers during the shoulder seasons; too cold in deep winter, too hot at the peak of summer.
Warm room / summer: the window for pink and yellow oyster.
Winter: a heat mat or a small seedling-heat source under colonizing blocks keeps the spawn run warm; a heated grow tent lets you run warm growers off-season.
Summer heat waves: cool growers stall or abort pins above their window — grow warm species then, or fruit in the coolest room you have.

A cheap min/max thermometer in your fruiting space tells you more than any guide can. Watch the overnight low and the afternoon high, not just the moment you check.

Spore safety

Wear an N95 mask when handling spawn or opening fruiting chambers, and ventilate the room. Repeated spore exposure can cause hypersensitivity pneumonitis (“mushroom worker’s lung”) — and cooler fruiting rooms with poor airflow are exactly where spores accumulate. See the mushroom worker’s lung N95 guide.

Bottom line

There’s no single “mushroom growing temperature” — there’s a warm colonization number (~20–24 °C for most species) and a cooler, species-specific fruiting window. Match the species to the room and season you actually have: cool growers for the basement and shoulder seasons, warm growers for summer. Get the fruiting number right and the yield follows.

See also: Mushroom growing conditions chart — temperature, humidity, fresh air, spawn rate, and timing for every species. How to grow oyster mushrooms in Canada — the bucket method, climate notes, and suppliers. Which mushroom should you grow first? — pick a species that suits your space.