Optimizing off-season flower production in chrysanthemum cv. Bidhan Shweta by synergistic effects of pinching and artificial short days

Chrysanthemum, being a short-day plant, has a limited flowering period in the subtropical climate of North India, restricting its year-round production. Therefore, the current study was initiated to explore the effects of photoperiod manipulation and pinching strategies on the off-season production of this specific genotype. The experiment was laid out in a Completely Randomized Design with nine treatment combinations comprising three photoperiodic conditions (natural, artificial short days from April, artificial short days from June) with three pinching levels (no pinch, single and double). Results suggested that treatment T4 (Artificial short days from April + no pinch) proved to be most effective for early flowering, as it took the least number of days for flower bud initiation at 74.56 days and 100% flowering at 122.12 days. But this earliness in flowering compromised the plant’s aesthetic pot mum quality, resulting in a reduced number of branches (2.60), the minimum number of flowers per plant (22.07), and the smallest flower size (4.32 cm). Whereas, treatment T3 (Natural photoperiod + double pinch) noticeably delayed flowering (192.82 days) but excelled in quality pot plant attributes like number of branches (7.65), maximum plant spread (33.94 cm), number of flowers per plant (64.41) and largest flower size (6.76 cm). The study concludes that the choice of treatment depends upon the grower’s specific objective. For those who want early, off-season flowering to secure higher market prices, treatment T4 is the best option. Contrary, if the objective is to produce aesthetically appealing quality pot mums for the main season, then treatment T3 is recommended.