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How much should a 5 lb block produce? Growers answer that with biological efficiency (BE), the standard yield measure in mushroom cultivation. Enter your dry substrate weight and species to see a typical yield range, then add what you’ve harvested to see how your results compare.
What is biological efficiency?
BE = fresh mushroom weight ÷ dry substrate weight × 100. A BE of 100% means one pound of fresh mushrooms for every pound of dry substrate. Because fresh mushrooms are mostly water while the substrate is weighed dry, BE above 100% is normal for oysters.
Typical yields
| Species | Typical BE (all flushes) | From 5 lb dry substrate |
|---|---|---|
| Blue / pearl oyster | 75–150% | 3.75–7.5 lb |
| Pink / golden oyster | 50–100% | 2.5–5 lb |
| King oyster | 50–100% | 2.5–5 lb |
| Lion’s mane | 50–100% | 2.5–5 lb |
| Shiitake | 50–100% | 2.5–5 lb |
| Reishi | 10–25% | 0.5–1.25 lb |
The first flush usually gives about half the total. Yields depend heavily on strain, supplementation and how well conditions are held.
Fresh vs. dried weight
Most mushrooms are about 90% water, so dried weight is roughly one-tenth of fresh weight — 1 lb of fresh oysters dries to about 1.5 oz.
FAQ
How many flushes can I expect?
Two to four for oysters and lion’s mane on supplemented sawdust; shiitake blocks can give several flushes with a soak between each. Later flushes get smaller.
How do I improve BE?
Supplementation (bran or soy hulls), correct moisture, a healthy spawn rate and good fresh air during fruiting make the biggest difference. Change one variable at a time and log results.
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