This study was carried out to determine the effects of 8 different planting-dates (22 September, 22 October, 22 November, December 22, January 22, February 22, March 22 and April 22) and 4 photoperiods (natural, 14, 15 and 16 hrs) on the growth and flowering of Gypsophila paniculata L. 'Perfecta' under controlled glasshouse conditions at the Alata Horticultural Research Institute (Erdemli, İçel-TURKEY). The times from planting to harvest were longer in autumn and in early winter plantings than in winter and in spring plantings under a 16-hr photoperiod. Suitable planting-dates were, seasonally, September 22 and October 22 in autumn, February 22 in winter and March 22 in spring. According to all criteria used in the study, the best results were obtained from the plants grown under 16- and 15-hr photoperiods, respectively. A 14-hr photoperiod was not conducive to obtaining desirable yield and flowering quality from G. paniculata L. 'Perfecta' plants during winter and early spring. The results concerning the time from planting to harvest also indicated that the flowering of the plants grown under the natural short photoperiod depended upon the beginning of the natural long-days. For that reason, there were no significant differences in the flowering dates of plants grown under a natural short photoperiod on different dates.

This study was carried out to determine the effects of 8 different planting-dates (22 September, 22 October, 22 November, December 22, January 22, February 22, March 22 and April 22) and 4 photoperiods (natural, 14, 15 and 16 hrs) on the growth and flowering of Gypsophila paniculata L. 'Perfecta' under controlled glasshouse conditions at the Alata Horticultural Research Institute (Erdemli, İçel-TURKEY). The times from planting to harvest were longer in autumn and in early winter plantings than in winter and in spring plantings under a 16-hr photoperiod. Suitable planting-dates were, seasonally, September 22 and October 22 in autumn, February 22 in winter and March 22 in spring. According to all criteria used in the study, the best results were obtained from the plants grown under 16- and 15-hr photoperiods, respectively. A 14-hr photoperiod was not conducive to obtaining desirable yield and flowering quality from G. paniculata L. 'Perfecta' plants during winter and early spring. The results concerning the time from planting to harvest also indicated that the flowering of the plants grown under the natural short photoperiod depended upon the beginning of the natural long-days. For that reason, there were no significant differences in the flowering dates of plants grown under a natural short photoperiod on different dates.