Over the last 30 years, some authors have reported no response or negative responses of K uptake to KCl fertilizer application. This situation is usually observed in soils whose exchangeable calcium content is very high in proportion to total exchangeable cations, a kind of soil common in the plantation of Indupalma Ltda. near San Alberto (Cesar). Since 1960, results from fertilizer trials carried out in the plantation led to the conclusion that negative responses were linked to the native chlorine deficiency; correcting the deficiency with chloride increased the uptake of potassium, calcium and magnesium, whose contents increased in the trunk, petiole and rachis of the fronds. Only K leaflet content did not respond to fertilizer. Since 2009, measurements of rachis K content in a factorial fertilizer trial confirmed a positive trend with KCl applications. On the basis of these preliminary results, periodic rachis sampling was undertaken to monitor K nutrient status in commercial blocks. According to figures presented by various authors and to its own research results, Indupalma is now considering that a minimum K content of 1 % DM in the rachis is suitable to guarantee acceptable K nutrition.