Most flowers that remain open when not in direct sunlight and that won't quickly wilt can be used in flower arrangements. Popular flowers for arrangements have sturdy stems so they won't break while being arranged and will at least last several days in water. Some flowers, like poppies, need to have their stems seared to stay fresh. Others, like amaryllis, have hollow stems that need to be filled with water before placing in a vase. But most flowers need no special treatment for using in arrangements.
Tall and Spiked
The tall spikes of flowers such as snapdragons, larkspur, delphinium and orchid sprays give height to an arrangement. Snapdragons come in lots of colors including red, yellow, white, purple and pink. Their stems are up to 24 inches high with flowers on the upper 12 inches, and often curved slightly. Larkspur blooms in pink, white, purple and true blue. Delphinium, which comes in shades of blue, isn't often found at florists. Its stalks are up to 5 feet high with flowers on the upper 18 inches. Delphinium is a stunning flower, but can be overpowering in arrangements. Orchids last up to two weeks in arrangements if the water is changed daily.
Large and Showy
Large flowers such as hydrangea, sunflowers, peonies, orchids, gerbera daisies, calla lilies, oriental and Asiatic lilies add drama to large flower arrangements. They also look elegant when massed in arrangements all by themselves. Keep the large size of sunflowers and lilies in mind when arranging flowers. You don't want to hide the smaller flowers.
Flowers like roses, carnations and chrysanthemums last for up to 10 days in arrangements if the stems are cut and the water changed daily. They are found year round in florists and the floral department of grocery stores. With the exception of Valentine's Day and Mother's Day, they are also reasonably priced. None of these flowers bloom naturally in blue, but can be dyed with floral spray or by placing their stems in water and dye.
Waxflower has small pink flowers with darker pink centers and waxy petals. Alstroemeria, also called Peruvian lilies, aren't lilies at all but perennials from tubers. They're shaped somewhat like azaleas and are about the same size. Their flowers are usually variegated with stripes of contrasting colors. Gypsophila, also called baby's breath, is a common flower used as filler for arrangements. It blooms in pink and white single flowers and white double flowers, which are use most often in arrangements. Tuck these filler flowers into the bouquet last to fill in any gaps.