Cut an inch off the stems of the main flowers at an angle with a pair of scissors or a sharp knife. Cutting stems at an angle allows the flowers to absorb water more efficiently. It is best to cut just one inch off the stems because these flowers need their long stems to fit beautifully into the tower vases. Avoid overcutting them.
Select a theme for your arrangement, and choose flowers accordingly. Tower vases can feature wildflowers that overflow the vase or elegant bouquet-style arrangements. Roses are popular flowers for tower vases because of their long stems and the sophisticated style they bring to the table when arranged together.
Insert a few stems of filler flowers into a vase filled with water. Scatter them around the vase so they serve as a layer for the main flowers. Filler flowers include hypericum berries, asters and baby's breath. It is best to insert these filler flowers first because they may be harder to insert on the outer layer of the arrangement after the main flowers are added.
Add the main flowers of the bouquet into the center of the vase, gently lifting the ones with dark or large petals to emphasize their presence in the vase.
Insert more filler flowers between the main flowers to make the arrangement look more coordinated.
Cup each of the main flowers in your hand to straighten their petals and secure their positions in the vase. Make sure that there are enough flowers in the vase to make the overall centerpiece look like a grand burst of flowers, instead of paltry flowers stuck into a vase.