Pollution of the environment, especially groundwater, may be reduced by proper fertilizer management, based in part on crop removal. The weights and concentrations of nutrients in tissue components of cut-flower roses (Rosa hybrida L.) were determined to assist in developing a fertilizer management system that sustains a high level of production but also is environmentally friendly. Harvested flower stalks of the cv. Royalty were cut to 45-cm length, and sectioned into 15-cm units, from which blossom, leaf, and stem components were separated, weighed, and analyzed for nutrients. The flower represented 28.5%, leaves 46.0%, and stem 25.5% of the total weight of the stalk. Upper leaves had the highest levels (g·kg-1) of N (29.3), Ca (21.8), and Mg (3.0), and (mg·kg-1) Fe (74) and Mn (71). The flower was highest in K (18.4 g·kg-1), P (3.0 g·kg-1), Zn (29 mg·kg-1), and B (23 mg·kg-1). Annual removal of nutrients by 45-cm flower stalks totaled: 256.2, 187.5, 116.3, 30.0, 26.0, and 21.1 kg·ha-1 of N, K, Ca, P, Mg, and S, respectively. Micronutrients removed per annum totaled 700, 470, 260, 200, and 190 g·ha-1 of Fe, Mn, Zn, Cu, and B, respectively. Assuming 50% recovery of applied N and 80% of K, a total annual application of N at 512 kg·ha-1 and K at 234 kg·ha-1 may replace the amounts removed. However, actual rates of N and K, as well as other nutrients applied, should be adjusted based on soil and tissue analysis results. Removal of nutrients will be greater if stalks harvested are >45 cm in length, which may necessitate additional nutrient application, depending on soil conditions.
