1. Plant performance is driven by nutrient availability. So far, studies on plant nutrient relationships mostly focused on nitrogen (N) and phosphorus (P), whereas potassium (K) received less attention. We evaluated whether plant responses to variation in nutrient availability is similar or different for the nutrients N, P and K and whether the same plant traits are decisive for the competitive ability of species along gradients of N, P and K availabilities. 2. We studied plant trait responses of three temperate perennial grass species (Alopecurus pratensis, Agrostis capillaris and ...