Effects of Shoot-bending in Relation to Root Media on Cut- Flower Production in Roses

Cut-flower production of Rosa hybrida ‘Kardinal’ and ‘Fire and Ice’ were compared between two canopy management regimes: shoot-bending and hedgerow without shootbending, and between hydroponics and non-hydroponic (UC Mix) culture with a tensiometer-based irrigation system. We observed the number and length of all harvestable flowering shoots from September 1997 to August 1999 in order to assess productivity and quality. Shoot-bending resulted in increased stem length of individual flowering shoots in both cultivars. However, this treatment also resulted in significantly fewer harvestable flowering shoots. In ‘Fire and Ice’, plants grown in hydroponics produced a greater number of harvestable flowering shoots in comparison with the plants grown in UC Mix. On the other hand, ‘Kardinal’ plants did not exhibit any difference in the number of harvestable flowering shoots between these two treatments. Both cultivars did not show difference in stem length of flowering shoots between hydroponics and UC Mix. We calculated the value of each shoot based on a formula developed to simulate the market value of each stem. With ‘Fire and Ice’ the improvement in stem lengths did not offset the economic loss due to the reduction in flower number under shoot-bending. For ‘Kardinal’ there was no significant difference in economic value between shoot-bending and non-bending.