Nothing says it's the holiday season quite like a cheery, blooming poinsettia plant! Native to Mexico, poinsettia plants are typically large, gangly shrubs in the wild. How Often Should You Water Poinsettias? patty_c // Getty ImagesIf you choose a fresh plant and give it the right conditions, your poinsettia plant will look good through the holidays until mid-January or beyond. Elizabeth Fernandez // Getty ImagesAs you may have heard, poinsettias are toxic to both cats and dogs.