Things You'll Need
Move poinsettias outside for the summer when temperatures remain above 60 degrees and all danger of frost has passed. To force poinsettias to "bloom," place them in a dark room for 12 hours a night beginning in October.
Stray light from a streetlight, or even a bathroom light turned on for a few minutes, may prevent the poinsettia from developing color.
Poinsettias flood the market during the winter holidays, claiming the title of best-selling potted flowering plant. These plants produce brightly colored bracts -- modified leaves -- that turn red, pink or white during the holiday season. Color is initiated by exposing the plants to complete darkness for 12 hours a day, starting in October. After the "blooming" period of six to eight weeks, poinsettias often lose their foliage as they enter dormancy. Many people cast the plant away, mistakenly believing it has died. Poinsettias can be grown for years with proper care.
Cease watering your poinsettia plant once the leaves have dropped. Move it to a cool location where it receives indirect light. Maintain temperatures between 50 and 55 degrees until spring.
Cut the plant back to 3 to 8 inches above the soil in the spring when new growth appears. Cutting back is not necessary, but will produce a dense, compact plant.
Repot the poinsettia in a plant pot one to two sizes larger than the original. The University of Rhode Island horticulture program recommends a mixture of three parts potting soil, two parts compost or peat moss, and one part perlite for a potting medium. Add 1 1/2 to 2 teaspoons of bone meal per quart of potting medium.
Move the poinsettia plant to bright light. Water when the soil feels dry to the touch 1 inch below the surface of the soil.
Apply water-soluble fertilizer designed for houseplants following the recommended application rate. Repeat on a seven- to 10-day cycle.
Pinch back when the first clusters of leaves are approximately 1 inch long. Pinch out the center leaves, allowing 4 to 5 leaves per cluster to grow. This forces branching and produces new clusters of leaves at the end of each branch. Repeat again when the new clusters have formed leaves 1 inch long.
Nannette Richford is an avid gardener, teacher and nature enthusiast with more than four years' experience in online writing. Richford holds a Bachelor of Science in secondary education from the University of Maine Orono and certifications in teaching 7-12 English, K-8 General Elementary and Birth to age 5.