No plant says Christmas quite like the poinsettia (Euphorbia pulcherrima). The world’s most popular flowering holiday plant, poinsettia has been a mainstay of the season in the U.S. for a century.

These bracts (the modified leaves often mistaken for flowers) turn vibrant colors — traditionally a bright red — in midwinter, making an excellent example of the importance of photoperiods.

The real flowers are small, yellow and appear at the tip of the stem surrounded by the bract. Look for new places to display your poinsettia. Place a plant on a side or serving table. Remove the ...