New York State Flower Industries , Inc
The philosophy and cultural manipulations of the 'one crop' carnation system have been described in previous New York State Flower Groiver Bulletin articles (1). Today, many growers use this method to produce carnations specifically for the Christmas and Valentine holidays. Our previous work indicated a varietal response to photoperiod, i.e., some cultivars flowered more rapidly and in a shorter cropping time than others (2, 3). For the 'one crop' system, the quicker-flowering cultivars would appear to be most desirable. It is interesting to note that for years carnation breeders have been selecting cultivars that do not crop, but rather have selected for contin uous production. We understand most carnation breeders are testing their new selections to see if they will fit the 'one crop' system as well. To determine the varietal response to photoperiod, 30 carnation cultivars (reds and pinks) were selected. The cuttings were supplied through the courtesy of Yoder Brothers, Barberton, Ohio. Four treatments were used: a) grown under natural days, b) grown under 18 hours, c) grown under 18 hours and suckered (all side shoots removed), d) grown under 9 hours. Because we have seen a difference in response between Ithaca and Long Island, the plants were grown in both locations and the results will be given for both.
Keywords: Photoperiod Cultivars Peak production Flower quality Ithaca and Long Island