One of the often underestimated aspects of cultivating white and brown mushrooms is evenness when filling phase 2 or 3 compost.

Whether the system is blocks, bags, trays or beds we often see that part of the surface is left unused because it is uneven.

This unevenly applied compost is one of the major causes of temperature differences, both in phase 2 and 3 compost.  In addition, if the compost layer is uneven when the compost is hydrated (which is usually necessary after casing) such extreme differences can occur that the optimal moisture content is only reached in certain patches. So, too wet in some places and in too dry in others. This is caused by temperature differences in the compost (evaporation) and naturally the thickness of the layer itself. The same applies to the casing soil layer. The usual thickness here is between 4.5 to 5 cm. You can only achieve a uniform moisture content on a layer of casing soil of the same thickness all over the growing surface. If the compost layer has already been applied evenly it’s not that difficult to apply an equally even layer of casing on top.

Special attention should be paid with blocks and bags here. The growing medium is often applied less carefully in block and bag cultivation, and so particularly in the first flush a larger or smaller part of the growing surface is not utilised, or the mushrooms start to form too deep and become soiled. But if a head filling machine is used to fill beds, attention must also be paid to creating an even layer. If caccing is applied with the compost this is usually done mechanically with this system. If the compost layer is not perfectly smooth, then the cacing applied during filling will also be irregular and any ruffling will also be uneven.

The result is patches of mushrooms growing too deep in the compost where there is too little mycelium and localised patches where the casing soil is covered by too many mushrooms because of too much compost. Under these circumstances it is impossible to harvest a good quality, good yield from every part of the bed.

Evenly filling the compost and casing soil is therefore the foundation for each growing cycle time and again.

Photo: Special attention should be paid with blocks and bags.