Gypsum

Phosphor gypsum
It’s hard to overestimate the role gypsum plays in the compost preparation process. Even though it’s used in relatively small amounts — about 60 kg for a ton of compost, gypsum plays a decision role in the formation of the compost’s structure and pH level. The pH level, in turn, determines the content of nitrogen in the compost. It’s a very important indicator for the nutrition of mushroom mycelium. The point is that the mushroom mycelium assimilates organic nitrogen, and can «eat up» the ammoniac one. But when the pH level is high, the ammoniac nitrogen can turn into free, gaseous ammonia which is a poison to mushroom mycelium. One of the most important indicators of compost is a complete absence of the ammonia odor. It’s best to use ordinary construction gypsum. Phosphor gypsum can be used, but it’s necessary to increase the amount of it applied. 40 kg of phosphor gypsum have to be applied to a ton of compost. Usually, the exact amount gypsum to be applied is determined by the quality of the raw materials.

Gypsum (packaged and not) has to be stored in a closed, dry room, so it stays dry and friable. The moisture of the gypsum mustn’t exceed 20%. And like any other supplement, gypsum has to be uniformly applied and distributed in the mass of compost.