Investigation of The Usage Possibilities of Leonardite as a Growing Medium

Growing medium is very important as it affects both the germination of the seed and the growth of the seedling. The most used growing medium for seedling growth in the world is peat. Because peat deposits contain a significant amount of carbon, growing mediums that can be used as an alternative to peat are gaining importance in terms of climate change. In this study, the possibilities of using leonardite 100% and its mixtures with different materials as a seedling growing medium for melon were investigated. As a result of the study conducted under greenhouse conditions, it was observed that the germination rate decreased when 100% leonardite was used as a growing medium. The highest plant height, stem length, leaf number, plant fresh weight, and dry weight were obtained from the use of 100% peat material. The highest stem diameter was obtained from 50% peat + 25% vermiculite + 25% perlite, and the highest root length was obtained from 50% peat + 50% perlite. There was no difference between the growing medium in terms of fresh root weight and dry root weight. As a result, it has been determined that it is not suitable to use 100% leonardite as a growing medium. However, it was observed that growing mediums 33% leonardite + 33% vermiculite + 33% perlite, 50% leonardite + 50% vermiculite, and 25% leonardite + 25% peat + 25% vermiculite + 25% perlite could compete with seedling growing mediums without leonardite.