The aim of this research proposal is to support well-founded potassium recommendations for Swedish table potatoes. The main issue today is that the recommendations are based on a few old experiments which were carried out with old management practices. There is a general practice among Swedish farmers to supplying more K than the potato plant needs for optimal growth in order to avoid quality issues. However, there are no or few research results supporting this strategy. This research proposal focus on studying yield- and quality related parameters in three potato cultivars over three years. This experiment will show whether adjustments in the recommendation system is needed or not. It may also indicate which K levels that would be appropriate to recommend.