Dahlia variabilis, commonly known as the garden dahlia, is a tender, tuberous perennial often grown as an annual, prized for its spectacular diversity of flower forms and vivid colors. Plants typically grow 1 to 5 feet tall with a spread of about 1 to 3 feet, forming bushy, upright clumps with hollow, branching stems and deep green, ovate leaves that can measure 4 to 8 inches long with coarsely toothed edges. The blooms are the main attraction, ranging from small 2-inch pompon types to massive decorative or dinner-plate forms that can exceed 10 to 12 inches across, borne singly on long, sturdy stems that make excellent cut flowers. Flower shapes vary widely—single, anemone, cactus, ball, and formal decorative forms—appearing from midsummer until the first frost. Underground, the plant develops clusters of fleshy tubers that may reach 2 to 4 inches long, which store energy for regrowth. Dahlias thrive in full sun with at least 6 to 8 hours of direct light daily and prefer rich, well-drained soil. Proper spacing of about 18 to 24 inches between plants ensures good air circulation, while staking is often needed for taller varieties with large blooms.