New methods for organic raspberry production in polyethylene tunnels

Raspberries for the fresh market is a new and very profitable crop in Norway, and the production in polyethylene tunnels is increasing rapidly. In Norwegian organic production, the experience so far is that using tunnels is a prerequisite if growing for t he fresh market. The project focuses on the major bottlenecks in organic tunnel production of raspberries. The project will develop methods for controlling the most damaging pests (raspberry beetle, aphids and mites) and methods for secure and efficient s upply of organic nutrients in tunnels. The research on raspberry beetle is a co-operation with Sottish Crop Research Institute. An important task in this project is to extend the growing area for tunnel production further north, by utilizing the long coa st of Norway. Main growing area for raspberries in Norway is in the Western part of Norway, (~ 61º N), where the climate has proved to be very suitable for raspberry production. Going further north along the coastline the summer gets cooler, but the winte r climate is quite similar. In Nordland (65º N), the raspberries grow well, but the fruits get damaged of rain and wind annually. In Troms, (68º N), the temperature sum during growing season is too low for outdoor production, but tunnels may render raspbe rry production possible in Troms. The project will develop methods for early growth start, for protection against frost and for extending the season. Different types and combinations of covers and reflective mulches will be tested for that purpose. The project will also obtain more knowledge about climatic and environmental impact on fruit quality, and includes analyses of potential health beneficial components in berries, which is important for the future marketing of the crop. The methods researched i n this project will also have a potential for use in conventional growing, and conventional as well as organic growers are participating.