An experiment was conducted in 2014-2015 to determine the effect of different horticultural substrates on mineral nutrient concentrations in the rhizomes of ginger (Zingiber officinale Rosc.) grown in a greenhouse of the Department of Horticulture at the University of Warmia and Mazury in Olsztyn. Ginger is a herbaceous perennial plant of the family Zingiberaceae, which is known for its medicinal properties. The health benefits of ginger have contributed to its growing economic importance in many regions of the world. However, due to its high temperature requirements, ginger is unable to grow in cold regions with adverse climatic conditions. For optimal growth, the species needs a nutrient-rich substrate saturated with water. Ginger can be grown in high-moor peat and coconut fiber or coir, which provide a steady supply of nutrients, water and air. Optimum environmental conditions stimulate the growth and improve the quality of ginger rhizomes. Three types of substrate were analyzed in the study: peat, coco coir and a mixture of both substrates at a 1:1 ratio. Ginger rhizomes were pre-sprouted in a greenhouse. The recommended cultivation practices for ginger were applied. Ginger roots were assayed for macronutrient content. The roots of ginger grown in coir had the highest concentrations of P, K, Mg and Ca. In all treatments, ginger roots were characterized by favorable Ca:Mg and Ca:P ratios, and slightly widened K:Mg and K:(Mg+Ca) ratios.

23.1.2018