How do you preserve a poinsettia?
Move to a colder place where the temperature never goes over 60 degrees and out of sunlight. Keep it indoors if you live in dry and hot areas of the country. Sometime in May, repot the poinsettia in a bigger container. Cut all the stems down to about four inches.
To preserve your pointsetta, keep the soil moist, a cup of water once or twice a week will do. Allow water to drain from the roots by removing the foil around the base. Be careful with leaves, as they'll quickly turn brown when damaged. Leaves will fall through the winter months, this is normal.