Effects of expanded clay (Leca) and Styrofoam as inorganic growing media substances on growth and development of Spathiphyllum wallisii

The present study was conducted to evaluate the effect of expanded clay (Leca) and Styrofoam on the physical characteristics of growing media and their relationship with the growth of Spathiphyllum wallisii. The experiment was laid out in a complete randomized design (CRD) with 9 treatments and 3 replications. Cocopeat and peat moss combined with different proportions of inorganic materials Leca and Styrofoam were used as conventional media for the growth control. Growing indices of plants consisting of the number of leaves, shoot length, the fresh and dry weight of shoot and fresh and dry weight of roots, and physical characteristics of the media including bulk density, particle density, total porosity, water retention and air space were determined in this work. Chemical characteristics of the media including total nitrogen, absorbed phosphorous, and absorbed potassium, organic carbon, pH, and EC were also evaluated. Our results show that growth of the plant is much better in control media containing 40% cocopeat and 60% peat moss. Moreover, Leca and Styrofoam can be used as additives in the media, but the suitable proportion Leca and Styrofoam in the growing media was 25% because an excessive amount of these substances led to a change in the physical characteristic of the media and a drop in the growth rate of Spathiphyllum wallisii. Moreover, using more than 25% of these substances made a change in the volume of pots, leading to their reduced stability and some difficulties during their irrigation and shipment to the greenhouse.