Curing Pile Irrigation Calculator

No compost-specific evaporation standard exists. During curing, microbial activity is low and the pile is near ambient temperature, so evaporative losses are much lower than during active composting.

For curing piles, 0–2 inches/month is a reasonable estimate for most climates. If local Class A pan evaporation data is available, that is the preferred input for site-specific design.

If pan data is unavailable, FAO Irrigation & Drainage Paper No. 56 (Allen et al., 1998) reference ET₀ values can serve as an upper-bound proxy — but note these were developed for crops, not compost:

• 0.5–1.5 inches — Cool or humid climates
• 2–4 inches — Temperate climates
• 4–8 inches — Hot or arid climates

Leave at 0 to exclude evaporative losses from the estimate.