Dec 07, 2019 ... If you live in the northern hemisphere, the critical day length signal for most poinsettia varieties to set bud or initiate their flowers occurs some ...
This critical day length (CDL) varies between plant species. For example, the familiar poinsettia has a CDL of 12 hours and 15 minutes. Once days reach the ...
Dec 07, 2019 ... new poinsettia cultivars have been introduced to commer- cial producers .... ent critical daylength than other poinsettia cultivars. Patranella et al ...
Dec 07, 2019 ... Although the poinsettia bracts may not be fully expanded, they should be showing ... The critical photoperiod occurs for flower bud initiation when the natural day ... Above 60 degrees, the day length must be rigidly controlled.
For example, poinsettias and chrysanthemums develop vegetative growth when the ... By knowing how daylength affects plant development in photoperiodic ... or flower more rapidly, when the photoperiod is longer than a critical duration.
Dec 07, 2019 ... Re-blooming a poinsettia the following Christmas is not easy, but it is rewarding ... In the Midwest, that critical day length occurs about Sept. 25.
Short-day plants --Poinsettia, chrysanthemum, goldenrod, ragweed, and ... the day length is LONGER than some critical day length (or more precisely, the night ...
Dec 07, 2019 ... bloom when the length of daylight (the photoperiod) drops below a particular ... rice, soybean, onion, violet, Christmas cactus and poinsettia. The critical threshold varies among plant species, but is often around 12 hours.
Examples are chrysanthemums, poinsettias and Michalmas daisy. 2. Long?day plants will be induced to flower only when the critical day-length is exceeded.