Agronomic strategies for the organic cultivation of potatoes for processing into high quality French fries and potato chips

Summary

In order to achieve the successful cultivation of potato raw material to be processed into French fries and crisps, the high quality standards set by the processing industry have to be fulfilled and high tuber yields attained. In a cooperative research project, different strategies for the cultivation of high quality potato raw material for processing were examined under the conditions of organic farming.
The choice of variety was found to be the most important agronomic instrument for the organic farmer to secure high tuber yields and quality. Varieties Agria and Marena can be recommended as they gave high tuber yields of the required size grade and also high French fry quality both at harvest and after storage. With regard to processing into crisps, cv. Marlen is highly suitable because it was observed to have good quality of raw material even after storage. On the other hand the level of reducing sugars in tubers exceeded the maximum tolerable concentration in relation to the maturity stage at lifting.
Furthermore, results confirm that any available agronomic measure to improve nutrient and water availability, but also seed-tuber treatment, has to be exploited in order to secure high yields at a satisfying quality level. Leguminous crops (field peas (Pisum sativum L.) with a following catch crop and ryegrass-clover leys) can be recommended as preceding crops. The management of ryegrass-clover leys (cutting or mulching) does not have a significant impact on tuber yield, grading or quality. Agronomic measures did influence processing quality, yet the impact of the weather conditions on crop development was much more important.
In summary, it can be stated that organic potatoes for processing can be cultivated successfully when site- and farm-specific conditions are considered.