Snapdragons are tender perennials, meaning that they may be annuals in areas other than USDA Hardiness Zones 8 and 9, according to About.com. They are also poisonous when ingested.
The botanical name for a snapdragon is Antirrhinum majus, and Antirrhinum is Latin for "pig's snout," according to About.com. They have brightly colored blooms that start to flower from the bottom of the stalk to the top. They flower in the spring season and prefer full sun or partial shade environments. Dwarf varieties can be as small as 6 inches, while common varieties can be as tall as 4 feet high.