The flowers measure from less than 2 inches to more than 8 inches in diameter. Colors range from pure white and pastel tints to bright shades of red, yellow, orange, red, and purple. Dahlias can be started from seed, rooted cuttings or dormant tuberous roots. Although dahlia seedlings are not difficult to grow, they do require 12 to 14 weeks before they bloom. Thus, it's a good idea to start dahlia seeds indoors in March to have adequate sized plants for May planting.
Most gardeners find it more convenient to purchase plants or tuberous roots.
Dahlias should be planted in a well ventilated, sunny location that is protected from strong winds. Plant dahlias after the danger of spring frost is past. To plant the tuberous roots, dig a hole 6 to 8 inches deep and large enough to accommodate the root. Lay the root flat with the bud or growing point up and cover the root with 2 inches of soil. Continue to fill in the hole as the plant grows.