Poinsettias are value for money because they’re capable of holding their colour throughout the winter.
In keeping with most indoor pot plants that bloom throughout this period, they enjoy a position in full daylight and a constant 12C to 15C temperature.
Vastly fluctuating temperatures are not to their liking, and it’s best to water them from the base. Too much moisture around the neck, accompanied by even the slightest bruising of tissue, can lead to disaster.
The best solution is an individual drip tray for every pot or standing several plants on a long tray with pea gravel. Add water and keep the level topped-up so the gravel is constantly moist.
Mass produced pot plants, such as poinsettia, are so easily replaced that it’s tempting to discard them once the bracts fade. However, you could accept the challenge of perpetuating one.
In late February prune each main stem by half, withhold water and move the plant out of direct sunlight until May. Then re-pot it in fresh compost and start watering. In September it needs 14 hours of darkness each day for two months.