Why are they so hard to keep?
They are foreigners originating in Mexico,and don't like the English weather!
A bit like me at times Again like me: During the flowering period, they like to be kept out of direct sunlight, and protected from hot or cold draughts.
They prefer a night temperature of 16°-18°C (60-65°F) and a day temperature of 18°C (65° F)
The soil should be kept uniformly moist, possibly requiring watering 2-3 times a week.
Fertilize every 2 weeks with a solution of houseplant fertilizer at 1 tsp per gallon.
After blooming reduce the amount of water and allow the plant to go dormant.
Move poinsettia to cooler position but not below 10°C (50°F)