Rosa × hybrida 'Samantha' plants were planted in pots of three soilless and two soil-containing media. Soilless media consisted of coal bottom ash and composted hardwood bark in 1:1, 2:1, and 3:1 ratios. Soil-containing media were equal parts soil, peat, and coal bottom ash; and a control of equal parts soil, peat, and sand. Half the pots of each media were treated with a cover crop of Hordeum vulgare L. 'Barsoy' to simulate weathering and incorporate additional organic matter prior to planting the roses. Physical and chemical properties of all five original media were examined, and production indices of two harvests were measured; including stem length, flower bud diameter, fresh weight, days to harvest and average number of blooms per plant. Results to date indicate satisfactory growth in all treatments. The three soilless treatments have produced more stems with larger flower bud diameters and shorter days-to-harvest than the soil-containing treatments. However, the fertilization, and electrical conductivity of all treatments remains below normal. Moisture retention data also show the soil-containing treatments to have higher container capacity and easily available water. Cover-cropped plants also had shorter days-to-harvest, but in one of two harvests produced flower buds of smaller diameter.
Physical and Chemical Properties of Coal Bottom Ash (CBA) from Tanjung Bin Power Plant
