Getting last year's poinsettia to flower
Poinsettias are short-day plants. Short-day plants are vegetative during the long days of summer and produce flowers when days become shorter in the fall. In order for pointesettias to flower for Christmas, they must receive complete darkness from 5 p.m. to 8 a.m. each night from October 1 until the bracts show good color, usually around early December. Protect the plants from light by placing them in a closet or by covering with a cardboard box. When using cardboard boxes, tape over any openings to insure complete darkness. Exposure to any type of light between 5 p.m. and 8 a.m. will delay or possibly prevent flowering. During the reminder of the day, the poinsettias should be placed in a sunny south window. Keep the plants well-watered and fertilize occassionaly during the forcing period.
By the ISU Hort Department
Winter Rose Poinsettias - Reiman's Picks