It is as easy as it is extraordinary: many vegetables crops are much more frost hardy than they are supposed to be. They can be grown in unheated greenhouses during wintertime. In 2007, Wolfgang Palme started a research project in Austria at the Horticultural College and Research Institute, close to Vienna. He discovered that lettuces can withstand temperatures below -10°C and Japanese greens even -20°C. His trials treated a diversity of more than 70 different crops that were well suited for sustainable unheated winter production for a local fresh supply. Lettuces, radish, kales, onions and carrots are attractive winter crops for the fresh food market.
In the Core Organic Project GREENRESILIENT, trials are carried out to answer the question of whether or not this production system is also suited for other Central and Northern European countries. Crop rotations are designed for sustainable and low-energy growing systems. Northern countries lack light during the cold season. Timetables are needed that show sowing and planting dates for a local fresh winter supply all over Central and Northern Europe. Therefore, research stations in Switzerland, Belgium and Denmark are involved.
There is no doubt that we need a resilient and solid year-round local fresh supply of organic vegetable crops in the different climate zones of Europe. This project will help to make that possible.