The flowering of Dwarf Bearded Iris as a potted plant requires knowledge of the effect of chilling time and photoperiod on the plant. An experiment was conducted to determine what combination of these two factors would lead to flowering. The treatments were chilling time (0,4, and 8 weeks) and irradiance treatment (short day, long day, and HID lighting). Iris rhizomes were potted into 6 inch pots, kept moist and placed in a 4°C cooler for the various lengths of time. These were then transferred to the different irradiance levels and allowed to flower in the greenhouse.
The plants that received 8 weeks of chilling flowered earliest, followed by those that received 4 weeks of chilling. The plants that were placed under HID lighting flowered earlier than those that were placed under long day light treatment. The plants that received short day light treatment did not flower except for those that received-8 weeks of chilling.