Expected Total Yield
30.0 lbs
Substrate
27.0 lbs
Spawn
3.0 lbs
Flushes
3
10% is standard and economical. 15–20% colonizes faster and reduces contamination risk.
27.0 lbs
3.0 lbs
3
49 days
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Inputs
Result
6 bags × 5 lbs = 30 lbs total. Spawn: 30 × 10% = 3 lbs. Substrate: 30 – 3 = 27 lbs. Yield: 30 × 100% = 30 lbs across 3 flushes. Cycle: 14 colonization + 7 first pins + (2 × 14) = 49 days.
Inputs
Result
2 monotubs × 25 lbs = 50 lbs total. Spawn: 50 × 20% = 10 lbs. Substrate: 50 – 10 = 40 lbs. Yield: 50 × 75% = 37.5 lbs across 4 flushes. Cycle: 60 + 7 + (3 × 14) = 109 days.
A standard 5 lb fruiting bag needs 4.5 lbs of hydrated substrate and 0.5 lbs of grain spawn at a 10% spawn rate. For faster colonization, use a 20% spawn rate (4 lbs substrate, 1 lb spawn). The total bag weight stays the same regardless of spawn rate.
| Container | Total Weight | Substrate (10%) | Spawn (10%) |
|---|---|---|---|
| 5 lb Bag | 5 lbs | 4.5 lbs | 0.5 lbs |
| 10 lb Bag | 10 lbs | 9 lbs | 1 lb |
| Monotub | 25 lbs | 22.5 lbs | 2.5 lbs |
| 5-Gal Bucket | 20 lbs | 18 lbs | 2 lbs |
Most growers use a 10–15% spawn rate by weight. A 10% rate is economical and works well for fast-colonizing species like oyster mushrooms. Slower species like shiitake benefit from 15–20% to outcompete contaminants during the longer colonization period.
Yield depends on species and substrate quality. Oyster mushrooms yield up to 100% of substrate weight across 3 flushes (5 lb bag = up to 5 lbs mushrooms). Shiitake yields about 75% over 4 flushes, while lion’s mane yields about 60% over 2 flushes.
| Species | Total Yield (%) | Flushes | Colonization |
|---|---|---|---|
| Oyster | 100% | 3 | 14 days |
| Shiitake | 75% | 4 | 60 days |
| Lion’s Mane | 60% | 2 | 21 days |
| King Oyster | 80% | 2 | 21 days |
The total cycle from inoculation to final harvest ranges from 49 days for oyster mushrooms to 109 days for shiitake. Oyster mushrooms colonize in about 14 days with first fruits at day 21. Shiitake takes 60 days to colonize with first fruits around day 67.
The best substrate depends on the species. Oyster mushrooms thrive on pasteurized straw, which is cheap and easy to prepare. Shiitake and lion’s mane prefer supplemented hardwood sawdust. All substrates need proper moisture content of 60–65% by weight.
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Last Updated: Mar 16, 2026
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