Sizu Riatto
Flush Hour · Chapter 12

Pick a Grow

Pick the container you have and get the whole recipe for it in one go: what to buy, what to weigh, what to heat, and what to call on harvest day.

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Opens on the book's tote. Pick another grow above, or size your own by its dry straw, wet straw or volume.

Size each one by its dry straw, its wet straw, or its volume

The recipe (the book's)

Enter the dry straw, the wet straw or the volume, then press Calculate.

The formula

  • Dry straw = as typed; or wet straw × (1 − target); or volume × fill ÷ 100 × packed density ÷ 1,000
  • Straw to buy = dry ÷ (1 − moisture as bought); wet straw = dry ÷ (1 − target); water taken up = wet − bought
  • Spawn = wet straw × the spawn rate; bags = all the spawn ÷ one bag, rounded up
  • Pasteurizing water = dry straw × the ratio; heat = liters × 4.186 × 60 °C ÷ 3,600 kWh (15 → 75 °C)
  • Call = dry straw (g) × your BE ÷ 100; Bronze, Silver and Gold = 50%, 75% and 100% of the dry straw in grams
The book's worked example, Chapter 12. The book's tote: 1.80 kg of dry straw from 2.0 kg bought, 6.0 kg wet, 600 g of spawn, 32.4 L to pasteurize; call 900 g, Gold at 1,800 g. A 5 gal bucket (18.93 L) filled the same way holds about 0.61 kg of dry straw and takes 205 g of spawn. A 10 lb straw bag (4.54 kg wet at 70%) holds 1.36 kg dry and takes 454 g (1 lb) of spawn.
Check it. Weigh the dry straw your own container takes before you soak it: the volume route is an estimate, the scale is not.

Honest limits. The bucket and the bag are worked from published sizes with the book's own fill and density, not grown by us. Other species (lion's mane, shiitake, king oyster) need sterilized, supplemented sawdust and a pressure cooker: this calculator is for oysters on pasteurized straw. The book's tub, its straw and its harvests were worked out on paper from published figures, not grown by us: weigh your own. Prices are illustrative, as seen in November 2026 (US mid prices, with UK beside where they differ), shown without a currency sign; put in your own. No yield or profit is promised. Everything stays in your browser: no sign-up, nothing stored.