Vegetative Growth and Productivity of Potted Crocus sativus in Different Growing Media

Saffron (Crocus sativus) is the most expensive spice in the world and a valuable medicinal plant. In this study, the flowering, vegetative growth performance, and daughter corm formation of potted saffron were investigated in six growing media: loamy soil, silty soil, sandy soil, peatmoss, peatmoss + sandy soil, and peatmoss + foam. The highest values of the stigma fresh weight, the root weight, and the number and diameter of daughter corms were observed in plants grown in soil with a light texture, i.e., sandy soil or peatmoss + foam, although smaller daughter corms were produced by sandy soil-grown plants. Compared with loamy soil (heavy soil), the peatmoss + foam growing medium increased the leaf pigment levels and the number of leaves and daughter corms, and it produced the highest number of daughter corms with diameters of >= 2 cm. Compared with plants in other media, saffron plants grown in loamy soil had higher catalase and peroxidase activities but lower polyphenol oxidase activity. Overall, saffron could be cultivated and produced in growing media with various pH values (4.00-9.25), although a mixture of peatmoss and foam was the optimal growing medium for potted saffron production. These findings are beneficial for selecting the optimal growing media/soil for saffron cultivation in farmlands.