How to grow cordyceps mushrooms
Cordyceps militaris
Cordyceps militaris fruits on brown rice in jars at 64–72°F (18–22°C), with harvest about 45–60 days after inoculation. It needs light to fruit, and its cultures wear out.
By Derick · October 24, 2026
- Fruiting temperature
- 64–72°F (18–22°C)
- Humidity
- 70–90% RH
- Inoculation to first harvest
- About 45–60 days
- Grows on
- Brown rice or other grain in jars
Difficulty: Moderate. The jars need sterile work and a light schedule, and cultures lose the ability to fruit after a few transfers (PLOS ONE).
Cordyceps growing conditions at a glance
| Stage | Temperature | Humidity | Fresh air / CO2 | Light | Days |
|---|---|---|---|---|---|
| Colonization | 68–77°F (20–25°C) | 60–70% in one trial | Filtered lid stays on | Dark | About 10–15 |
| Primordia | 64–72°F (18–22°C) | 70–90% | Filtered lid stays on | 500–1,000 lux, 12 hours on, 12 off | Day 18–25 from inoculation |
| Fruiting | 64–72°F (18–22°C) | 70–90% | Filtered lid stays on | 500–1,000 lux, 12 hours on, 12 off | Harvest about day 45–60 |
Where these numbers come from
- Temperatures, humidity and light. A 2020 strain study summarizes the research: mycelium grows best at 20–25°C and fruiting bodies at 18–22°C, with 70–90% humidity, 500–1,000 lux to start fruiting and a 12-hour light, 12-hour dark cycle. The study itself colonized its rice medium at 22°C and 60–70% humidity in the dark (BioTechnologia).
- Colonization time. A 2017 trial kept rice medium in the dark at 23°C for 10 days before light (PLOS ONE); the 2020 study gives 15 days (BioTechnologia). Rootlab starts its kits' light cycle after only 3–4 days of darkness (Rootlab).
- Primordia formed 18–25 days after inoculation, depending on the strain (BioTechnologia).
- Harvest. India's ICAR mushroom directorate reports fruiting within 35–40 days, which may mean fruiting starts then rather than harvest (Office of the Principal Scientific Adviser). A Korean study kept its bottles under continuous light at 20°C for 50 days from inoculation (Mycobiology). Rootlab, a kit seller, harvests at about 55–60 days and keeps its kits at 18–20°C throughout (Rootlab). We give about 45–60 days to harvest.
- Fresh air. Rootlab keeps the filtered lid on at every stage (Rootlab).
What does cordyceps grow on?
Brown rice with nutrient liquid
Brown rice is the standard base; a 2020 study cites earlier work in which brown rice gave the highest fruiting-body yield (BioTechnologia). Rootlab mixes it with potato-infused water (Rootlab). Home growers grow C. militaris, not Ophiocordyceps sinensis, the wild fungus that grows on ghost moth caterpillars in the Himalayas (Stanford).
Rice with silkworm pupae
A Korean study used 60 g brown rice with 10 g silkworm pupae per 1,000 ml bottle, sterilized at 121°C (250°F) for 20 minutes (Mycobiology).
Other grains
Wheat, corn, millet and sorghum have also been used (BioTechnologia).
How to grow cordyceps, step by step
Inoculate with liquid culture
Researchers inoculate with liquid spawn (BioTechnologia). Work in a still air box and use a clean liquid culture; our syringe guide covers testing one first.
Colonize in the dark
Keep jars dark at about 72–73°F (22–23°C) for 10–15 days (PLOS ONE; BioTechnologia). Colonization is done when white mycelium covers the rice.
Turn on the light
Move jars to 64–72°F (18–22°C) under 500–1,000 lux, 12 hours on and 12 off (BioTechnologia). The mycelium turns from white to yellow, then orange (BioTechnologia; ScienceAsia).
Watch for primordia
Small primordia appear 18–25 days after inoculation, depending on the strain (BioTechnologia). Keep the filtered lid on (Rootlab).
Harvest
Harvest about 45–60 days after inoculation. Rootlab waits until at least three fruiting bodies are 4 cm (about 1.5 inches) long, then cuts them at the base (Rootlab).
What's different about growing cordyceps?
Light is the trigger
Light is the key environmental factor for C. militaris: it drives the orange color and the fruiting bodies themselves. Research puts the best intensity for starting fruiting at 500–1,000 lux, and mycelium grown in the dark stays white (BioTechnologia). Rootlab uses a 6000–6500 K white LED strip that doesn't heat the jars (Rootlab).
Cultures wear out
C. militaris cultures degenerate as you transfer them. In a 2017 trial, a strain began degenerating in its third generation, grew incomplete fruiting bodies in the fourth and grew only mycelium by the sixth (PLOS ONE). A 2024 study calls degeneration "frequent, irreversible, and inheritable" and treats a sectored colony as a sign of the mutations behind it (ScienceAsia).
Our advice: store an early-generation culture, start each batch close to it on agar, and don't keep transferring from your newest jar.
When and how do you harvest cordyceps?
Cordyceps is ready about 45–60 days after inoculation. Rootlab picks once at least three fruiting bodies are 4 cm long (it says this sign isn't always reliable), loosens the rice cake at around day 60, cuts the fruiting bodies at the base and stores them in a paper towel (Rootlab).
Yields are small. ICAR reports 12–14 g per 500 ml jar (Office of the Principal Scientific Adviser), and Rootlab 10–45 g fresh per container (Rootlab). The best of five strains in the 2020 study reached 8.95% biological efficiency, measured as dry mushroom weight over dry substrate, so it isn't comparable to the fresh-weight biological efficiency most growers log (BioTechnologia). None of our sources describes a second flush.
Common cordyceps problems
Mycelium grows but never fruits
The culture may have degenerated: by the sixth generation in one trial, only mycelium grew (PLOS ONE). Start again from an early-generation culture.
Mycelium stays white
White mycelium usually means too little light: colonies stay white in the dark and turn yellow under white light (BioTechnologia). If it stays white under a good light, suspect a degenerated culture: in a 2024 study, some crosses stayed white after a week of light and never fruited (ScienceAsia).
Deformed or no fruiting bodies in a warm room
Above 20°C (68°F), Rootlab says the fruiting bodies "will either deform or not grow" (Rootlab). Keep the jars and light cool.
Mold or slime on the rice
Rice and nutrient broth feed contamination and bacteria as readily as cordyceps. Use our contamination ID guide, discard the jar and tighten your sterile work.
Tracking a cordyceps grow in Hypha
Hypha links each culture and block you create as a transfer to its parent, so you can count how many generations a jar is from your stored culture before it starts to wear out. Compare each strain's success and contamination rates, and keep photos by grow to see when the mycelium turns orange. Its default reminders are the same for every species, so move the dates out for cordyceps' longer grow.
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Cordyceps growing FAQ
How long does cordyceps take to grow?
Cordyceps militaris takes about 45–60 days from inoculation to harvest: about 10–15 days to colonize in the dark, primordia at day 18–25, and fruiting bodies under light after that (PLOS ONE; BioTechnologia; Office of the Principal Scientific Adviser; Rootlab).
Can you grow cordyceps indoors?
Yes, cordyceps militaris is grown indoors, in sterilized jars of brown rice under artificial light. Rootlab's kits use a white LED strip, 14 hours on and 10 off (Rootlab).
What temperature does cordyceps need?
Cordyceps fruits at 64–72°F (18–22°C) and colonizes at 68–77°F (20–25°C) (BioTechnologia). Rootlab keeps its kits at 18–20°C and says warmer jars deform or don't fruit (Rootlab).
Is cordyceps hard to grow?
Cordyceps is moderately hard: the jars need sterile technique and a light schedule, and cultures degenerate after a few transfers (PLOS ONE). Start from a fresh culture or a kit.
Does cordyceps need light?
Yes, cordyceps needs light to fruit: about 500–1,000 lux on a 12-hour cycle (BioTechnologia). A Korean study used continuous light at 500–1,000 lux (Mycobiology).
Terms on this page
Sources
- PLOS ONE (pmc.ncbi.nlm.nih.gov/articles/PMC5657973)
- BioTechnologia (bibliotekanauki.pl/articles/2096987.pdf)
- Rootlab (rootlab.com.au/beginner-mushroom-growing-kits/how-to-grow-cor…)
- Office of the Principal Scientific Adviser (psa.gov.in/livelihood/10137)
- Mycobiology (pmc.ncbi.nlm.nih.gov/articles/PMC3769561)
- Stanford (sustainability.stanford.edu/news/climate-change-overharvesting-may-doom-pr…)
- ScienceAsia (scienceasia.org/2024.50.n4/scias50_2024074.pdf)
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