We evaluated the effectiveness of capillary‐wick samplers (PCAPS) for continuous monitoring of resident nitrate concentration in three 'soil‐crop‐climate'systems differing in soil type, land use and climate. These systems involved:(i) acid silty soils under a beech‐oak forest affected by heavy N‐NH4+ deposition in Belgium;(ii) silty soils under wheat cropping and a short rotation willow coppice plantation (SRC) in Belgium; and (iii) volcanic ash soils under plantain cultivation with and without urea fertilization in Colombia. The PCAPS
