Is poinsettia plant affected by the amount of sunlight they receive?

poinsettia plants have been observed to bloom during the days of December when the nights are longer than the day. are poinsettia plants affected by the amount of sunlight they receive? how??

Is poinsettia plant affected by the amount of sunlight they receive?
Poinsettia blooms in short days of winter, but you can determine it to bloom any time of year through light manipulation. You cover the plant with a black bag or a bucket to stop completely the light - for 14 hours/day. The rest of 10 hours/day you expose the plant to moderate light.


After the bloom period, the plant needs 2 months of resting, when all the leafes are changing the colour in the initial green or fall. Poinsettia needs a light spot, but without direct sunlight, temperatures 18-20 grade Celsius.
Reply:Poinsettias respond to the far red range of the light spectrum. The length of exposure to these rays affects hormones within the plant to cause it to go into a blooming cycle. Cool temperatures around 15 to 20 degrees C. seem to accelerate the process. I once forced a crop of poinsettias into flower in March for Epcot in Disneyworld using light control.