Now here's the tough part: Poinsettias won't flower unless they are kept in total darkness for 14 continuous hours per night for 8 to 10 weeks. Even momentary exposure to a streetlight or flashlight can delay or inhibit flowering completely. Starting October 1, keep the plant in a closet or an unused room at night or cover it with a box or heavy paper bag. The plant should stay in the dark from 5 p.m. to 8 a.m. Nighttime temperatures shouldn't fall below 60°F. From 8 a.m. to 5 p.m., it will need full sunlight, with daytime temperatures around 70° to 75°F. Keep watering and begin the feeding schedule again. After 8 to 10 weeks, the bracts should be flushed with color. Congratulate yourself on your patience and dedication, and give your rejuvenated poinsettia a place of pride in your holiday decorating!