Influence of geocomposite application on pH, EC and N, P, K, Mg and Ca contents in peat substrate in cultivation of selected ornamental shrubs

Decreasing water resources led to a search for new solutions facilitating sustainable management of containerized plant production. Geocomposite is a modern technology that absorbs water, utilizing a superabsorbent that is embedded within an openwork disc for structural support and enclosed in black geotextile for containment. This structure permits direct placement of the geocomposite in the root zone of plants, as well as minimizing any negative interactions between the superabsorbent and soil/substrate. The aim of this research was to assess the influence of geocomposite use with different fertilizer treatments (3 g Osmocote Plus 3-4M, 1.5 g Osmocote Plus 3-4M, 3 g YaraMila) on pH, EC and N, P, K, Mg and Ca content in peat substrate in the cultivation of Prunus pumila var. depressa (Pursh) Bean and Diervilla lonicera Mill. in an unheated hoophouse. In the substrates of both species pH was higher with the use of geocomposite, while the EC of these substrates was higher without. Except the Mg and Ca, the tested nutrients were in higher concentration in substrates with geocomposite. The highest pH in substrates of both species was noted in the 1.5 g Osmocote treatment, while highest EC occurred in substrates fertilized with YaraMila. N content in the substrates of both species was highest with 3 g Osmocote and YaraMila fertilization, while P, K, and Mg in YaraMila treatment. The results show that geocomposite application may increase pH and the concentration of monovalent ions, while decreasing EC and divalent ion concentration in the substrate. Moreover, despite the tendencies observed in substrates from Prunus pumila var. depressa and Diervilla lonicera, the numerical values of the results demonstrate that species can also modify the substrate properties.