Poinsettias will last through the holiday season if given proper care. Buy fresh plants that show no signs of leaf drop or wilting and protect them from cold air when bringing them home. Plants do best in bright, indirect light in a room that is kept between 65 and 70 degrees. Remove any wrapping that impedes drainage. Allow the soil to dry a little between waterings. Empty pot saucers to avoid standing water. Keep the plants away from cold drafts and heat registers.