Make sure the center rose rises slightly above the others to create a rounded effect to the rose cluster. Using the individual leaves, push the wire into the leaf edge and down into the floral foam. Cut the heather off the main branch into individual stems and place around the base of the rose stems, rising upward to the bottom edge of the roses. Using a long piece of the wire, wrap lightly from bottom to top to secure the heather fairly tightly against the rose stems. Do not wrap wire so tightly that the heather stems are damaged, but enough so that it doesn't show, and blends into the heather blossoms.
Mechanics are the items that make the design work, giving the designer control over the components.
Paints are available from hardware stores and craft stores. A grouping of topiaries can be used for maximum effect when creating a vignette, and several could be placed at intervals down the length of a dining table atop a mirrored or fabric runner, perhaps with votives, ivy, or ribbon streamers swirled along the table in between each topiary.