The classic red poinsettia is ever-present come December, and you can buy it as easily in the supermarket as the floral shop. Many shades of red are available, not to mention pink, creamy white, yellow, variegated and bi-colored.
Poinsettias are simple to care for. Put them in a bright window (but not in direct sun) and water the plants thoroughly when the soil surface is dry to the touch. (Discard any water that collects in the saucers because poinsettias don’t like wet feet.) The best temperature for poinsettias is between 60 and 70 degrees. Try to keep them away from hot, dry air or cold drafts.
The coloring often lasts until spring, but you can bring them back for an encore. When blooms fade (around May), cut the plants back to about 5 in. and set them in the garden for the summer. Water sparingly until new growth starts, then when needed. Add a water-soluble fertilizer every three weeks. To get your poinsettia to bloom in time for Christmas, keep the plant in total darkness for 14 hours a night from September to late November. One idea is to cover the plant with a cardboard box as soon as you get home from work and then uncover it when you leave the house the next morning.