Productivity of greenhouse roses following changes in soil moisture and soil air regimes

Following 2 years of different soil moisture and air regimes for ‘Baccara’ roses, the optimal regimes were chosen and kept uniform for each growth medium. These regimes were implemented for an additional year (1971–1972).Soil moisture and soil air regimes employed in previous years (1969–1971) had significant after-effects on flower yields in 1971–1972, but no effect on flower quality or weight. The effect of previous suboptimal moisture and air regimes was apparently due to the number of main branches formed per plant in the initial two years, which was unaffected after implementation of optimal regimes.Approximately 4 weeks after cessation of cutting, the root system consituted 11–15% of the total weight of the plant. While 65% of the root system in non-separated beds was located in a soil layer between 30 and 60 cm, only 27% were located above this layer.