Leachate Tables as a Tool for Monitoring Changes in Physical and Chemical Parameters of the Peat Substrate in the Cells of Nursery Containers

Measuring the physical and chemical parameters of substrates in the cells of nursery containers during production is difficult. Monitoring these parameters, however, is required for optimizing the use of substrates and their components in nursery production, specifically important in the progressive reduction in the use of peat. A new solution—leachate tables—for those studies is presented. The leachate tables enable the collection of liquid samples draining from individual cells in nursery containers during long-term irrigation and fertilization. During our 2-month-long experiment, changes in the physical and chemical parameters of the substrate were analyzed, as well as the process of accumulation of elements fed to the substrate via fertilizer and irrigation water. It was found that, due to the different cell volumes, filling the containers with the substrate under the same parameters of vibration and initial moisture resulted in different fractions of the substrate ending up inside the cells. In the smaller cells, the larger diameter fraction was dominant, and in the larger cells, the smaller fraction was dominant. This may have influenced the differences in air and water capacity of the substrate in cells of different volumes and confirmed the need for the selection of individual vibration parameters for the containers. In addition, over time, the granulometric composition of the substrate in the containers changed. Along with the systematic administration of elements via fertilization from the sprinkler ramp, their leachate content increased as a result of increased leaching from the substrate. With time, the physical parameters of the substrate in the cells stabilized, which may have affected the accumulation and leaching of elements during irrigation and fertilization.