Effect of different soil moisture regimes and canopy wetting on ‘Baccara’ roses

Abstract

The combined effect of different irrigation regimes and canopy wetting treatments on flower yield and flower quality was examined with ‘Baccara’ roses. Total yields of 390 flowers per m 2, of which 290 were of saleable quality for the period October–May, were obtained when the soil water tension at a depth of 15–20 cm was maintained below 4–6 centibar (cb). An increase in water tension up to 10–15 cb caused a 10 % decrease in yield. Wetting the canopy reduced the number of flowers and did not counteract the reduction in yield caused by the increase in soil water tension. Wetting the canopy slightly reduced plant surface temperature, mainly on dry and hot days. Wetting also increased the weight of flower buds obtained under irrigation treatments which maintained soil moisture tension below 5 cb (a low soil moisture treatment). The weight per unit length of flower stem increased when the canopy was wetted under all irrigation treatments. In spring, canopy wetting reduced the decrease in flower weight and in leaf area, and completely prevented the decrease in flower stem weight.