Summer growing on supplemented compost
The summer months require compost managers and mushroom growers to adapt to warmer and more humid weather conditions.
We have therefore asked consultant Henk van Gerwen to share his thoughts on summer growing with you.
In general during summer (warmer) periods, it is more difficult for mushroom growers to keep compost temperatures on desired levels. A common reaction is to stop supplementing, even though this causes yield reductions. However, there are a number of actions – direct and indirect – the mushroom grower can take to minimize the risk of overheating.
The direct actions are the things the grower can do at farm level.
The room that has to be filled with the new compost is the hottest room on the farm. It has just been cooked out and therefore the walls and floors still carry a lot of warmth. Immediately after emptying the house, close the doors and start washing the growing room with lots of water. Keep the doors closed while doing so.
After cleaning keep the doors closed just until the start of filing and pre-cool the room. This will also help against flies. Only open the door just before filling, but not before the whole filling region has been washed. Everything should be completely wet.
Another point is watering the compost during filling of phase III compost. On a good compost 4 to 6 litres of water per m2 can be given during filling. Not more. After that the compost needs to be cased with a good casing soil. The casing soil should be able to absorb, hold and release water. Straight after filling, close the doors, wash the house and start watering. Make sure that the casing soil reaches the maximum absorption level, but do not give too much water for the compost. There is no need to do so. The casing evaporation should be enough to cool the compost. The water itself is not the prime cooling factor for the compost.
Use climate controlled cooling (for evaporation) and check the absolute humidity of the outside air. If the air is warm but dry, it can be used. This dry air will let the casing evaporate and it will therefore cool the room. If the floor is kept dry, the casing soil will evaporate even more. If the absolute humidity outside is higher than the humidity in the growing room, only cooling should be used. At the same time set the fan to its highest speed. Evaporation is a combination of circulation and refreshing air.
If this does not help there are a few indirect options. Sometimes it is possible to get a compost with a longer incubation period. These composts are less active in the growing room. Keep in mind though that the compost yard needs more tunnel time for this.
A second option is to ask your ChampFood representative for a supplement with different/slower release patterns. In consultation with ChampFood International, it can be decided to switch to a customized supplement.