In the early spring, while the air and soil are still relatively cold, the mineralization processes in the soil take place so that organic matter does not release the nutrients indispensable for winter crops at that time to continue their growth and development. Not having the available nutrients, the crops begin to lag behind, and the final result is reduced yield. The best aid to young crops during that period is top dressing with mineral fertilizers ASN or CAN. Both these fertilizers contain nitrogen in the form of nitrates that plants can take in very quickly and incorporate them into their cells and thus continue to grow and develop undisturbed. In addition to the nitric nitrogen, both fertilizers also contain ammonia form of nitrogen whose characteristic is prolonged action with an additional advantage of slower rinsing into deeper soil layers. This advantage is particularly pronounced if there is a rainy period several days after the top dressing, which was common in previous years.