While the outside surfaces of permanent Venlo-type glasshouses are typically cleaned once a year, washing polythene tunnels presents greater difficulties. Now a Swedish company has developed a washing system for the roof of film greenhouses.
“It is known that growers, who often clean the greenhouse roof, achieve better growing conditions inside. The clean plastic allows more light transmittance, and more light means more growth”, said Bert Boye from INRHA, the company which has developed the new roof cleaner.
The company set out create a poly roof washing machine for greenhouses with double or single plastic films on the roof. ‘The technical challenges were many and complex, and it took three years before there were drawings and a concept to build for,’ explains the company, which has applied for a patent on 24 different parts of the new machine.
“This machine is now used at growers in Scandinavia; it is touring from Norway to Denmark and from Finland to Sweden to wash the roofs,” added Bert. “These growers would like to use as much light as possible, hence it makes sense to them to wash their roofs in time. Some of them even wash the roofs up to twice a year.”