If growers decide to use heavy casing soil to restrict the number of pieces the head filling machinery must be able cope with distributing the weight correctly over the beds. Not being able to handle the casing soil should never be a reason to use a different type! First investigate the reason. With the casing soil layer the surface structure is very important. The surface should have a structure which creates a microclimate. This means the pinhead is formed and protected in the casing soil surface. Avoid over-compacting the casing soil during levelling. Certain influences combined with casing soil quality can also compact the casing soil - pay attention here too. Growers should always try to prevent the casing soil being stuck to the compost. A casing soil layer that is too compacted offers too little or no capillary space. These spaces are very important for water absorption plus over-compacted casing soil restricts optimal CO2 and moisture exchange!
Jos Buth, C point