Snapdragons are among the best flowering plants for sunny borders and for cutting. Bushy and erect, they have glossy, lance-shaped, deep green leaves and flowers packed onto upright spikes. Snapdragon blooms have five lobes, divided into upper and lower “jaws”; by pinching the sides of the flower lightly, you can make the jaws snap open. Plants are at their best in spring and early summer. In regions with mild winters and hot summers, they bloom in winter and spring.
Several variations on the basic snapdragon have been developed: the double flower; the bell-shaped kind, with round, open flowers; and the azalea-shaped bloom, which is a double bellflower. All are available in many colors. Plants range from about 6 in. across for the smallest types to 2 ft. wide for tallest.
Tall and intermediate forms are superb vertical accents in borders. Tall kinds (to 2 1/2–3 ft.) include Rocket and Topper strains (single flowers) and Double Supreme strain. Intermediate (to 1–2 ft.) are Cinderella, Coronette, Minaret, ‘Princess White with Purple Eye’, the Ribbon series, Sprite, and Tahiti. Dwarf kinds (just 6–8 in. high) are effective as edgings in rock gardens and raised beds, or in containers. Look for the following: Dwarf Bedding Floral Carpet, Kim, Kolibri, and Royal Carpet. Bell-flowered strains have round, open flowers and include Bright Butterflies and Wedding Bells (both 2 1/2 ft.), La Bella (1 1/2 ft.), and Little Darling and Liberty Bell (both 15 in.). Azalea-flowered strains include Madame Butterfly (2 1/2 ft.) and Sweetheart (1 ft.). In a category of its own is the Chinese Lanterns strain: this bell-flowered snapdragon with trailing, cascading stems is ideal for hanging baskets.
Sow seeds in flats from late summer to early spring for later transplanting or buy plants at nursery. Set out plants in early fall in mild-winter areas, spring in colder climates. If snapdragons set out in early fall reach bud stage before night temperatures drop below 50°F (10°C), they will start blooming in winter and continue until weather gets hot.