Horticultural Science and Technology ISSN:1226-8763(Print) 2465-8588(Online) 원예과학기술지

This study was carried out to investigate the aging effects of coir dust (CD) and different origins of peat mosses (PM) on root substrate physical properties. The blending effects of CD or PM with various ratios of vermiculite (VL) or perlite (PL) on the changes in physical properties were also investigated. The physical properties of aged coir dust (ACD) compared to fresh coir dust (FCD) showed no significant differences in total porosity. But, container capacity increased from 59.6% to 71.1%, and air-filled porosity decreased from 30.1% to 18.9%. The total porosity of imported PM was, 83.8% in Estonia, 82.6% in Canada, 82.5% in Latvia, and 81.8% in Lithuania. The container capacity of Lithuanian PM was the highest with 75% followed by 73.1% in Canada, 71.8% in Latvia, 71.2% in Estonia, but the air-filled porosities were 12.5% ​​in Estonia, 10.7% in Latvia, 9.50% in Canada, and 6.90% in Lithuania. When the mixing rate of vermiculite to ACD or FCD were elevated, the total porosity was reduced and the elevation in ACD resulted in the quadratic decrease of air-filled porosity (R² = 0.6127, p ≤ 0.01). By increasing the mixing ratio of perlite to ACD or FCD resulted in the decrease of total porosity. Similarly, by increasing the quantity in mixing ratio of pearlite to ACD, decreased the container capacity with the quadratic tendency (R² = 0.5687, p ≤ 0.01). The elevation of mixing ratios of PL or VL influenced differently on total porosity, air-filled porosity, and container capacity in each of the imported PM. This is due to the particle size. In summary, ACD is more suitable for hydroponic cultivation of strawberry due to its lower air-filled porosity and higher container capacity compared to FCD. It is also better to increase the air-filled porosity to 15% or more by mixing PM with PL.