Many people deck the halls with poinsettias during the winter holiday season and flounder because they aren't sure how to maintain them after the festivities. Keep the poinsettia plants in the proper growing environment or you soon may be watching the leaves fall away because of stress. Eventually the poinsettia will enter dormancy, at which time it can be prepared to reflower when it awakens.
Remove any decorative foil or paper from around the outside of the planting container as soon as possible.
Place the poinsettia plant in a warm and sunny location away from any drafts.
Provide regular water for the poinsettia to keep the soil from drying out. Allow the water to run through the planting container and drain out of the bottom before placing the container back onto a drip saucer.
Mix the fertilizer with water according to package recommendations for the size of the planting container. Provide fertilizer for the poinsettia twice per month until the plant enters dormancy.
Watch for dormancy signs, which include dropping leaves and cessation of growth. Water the plant only to moisten the soil when the soil dries. Stop fertilizing it. Move the plant to a cooler location (approximately 55 degrees F) and keep it there until spring.
Remove the poinsettia from its dormancy location in the spring. Cut the plant back so that it is approximately 5 inches above the soil level. Place the poinsettia back in its sunny location and resume watering it on the previous schedule.
Assess the plant as it begins growing again. Resume fertilizing approximately once per week during the growing season when there is approximately 1 inch of new growth. Continue fertilizing the poinsettia once per week through the middle of December.
Prune the poinsettia to remove the top 5 inches of growth as it appears over the summer to encourage lateral growth. Remove another top 5 inches of growth if it occurs again before the growing season ends.
Place the poinsettia in complete darkness for 15 consecutive hours out of each 24-hour-period to encourage the plant to flower again. Begin the darkness regimen approximately 10 weeks before you desire flowers. Place the poinsettia in direct sun when it is not in the dark environment.