Nutrient availability influences key processes for plants in all ecosystems with nitrogen (N) and phosphorus (P) most limiting terrestrial ecosystems. Foliar N and P concentrations have been commonly used as indicators of plant nutritional status. Tropical forests are known to have the highest foliar N:P globally which mirrors a greater degree of P limitation compared to other forests. We tested how plants respond to chronic N and P fertilization by analyzing soil and foliar N and P concentrations from a long term fertilization experiment in Costa Rica. As foliar nutrient concentrations often reflect soil nutrient availability, we had found that this may not have been the case for our samples. Total soil N had not changed significantly but foliar N was affected. We also found that available soil P had increased with chronic fertilization but foliar P was unaffected. There was an overall species effect on foliar nutrient concentrations reflecting the plant specific response to nutrient additions. Here we have added to the knowledge of how plants in tropical forests respond to changes in nutrient availability is important to predict how they will respond to anthropogenic alterations in nutrient cycles, such as N deposition.