To create a poinsettia tree, follow these instructions: First, cut the larger blooms, leaving about 6 inches of stem. Sear them quickly to stop sap from dripping out. Sap should bubble under the candle flame, and the ends of the stems will turn black. You may also need to sear the points where larger leaves were removed along the stems. Insert each seared stem into a water-filled florist tube. Stems are hollow and will absorb water after being seared. Place the stems into the base of the ivy topiary. Then repeat this process with the medium-size and smaller poinsettia blooms, cutting the stems so they're about 4 inches long. Insert blossoms into the topiary, working your way toward the top. Once it's complete, care is simple—just add water to the tubes every few days, as needed.