More than 36 species of flowering plants are considered Dahlias. The dahlia plant can range in size from 1 foot to more than 8 feet and can produce flowers that can be as small as 2 inches or as big as 12 inches. Dahlia's are originally from Mexico and Central America and were used by the Aztecs as a food source and as a decorative plant.Dahlia roots were sent from Mexico to the Netherlands in the late 1800s. Unfortunately only one root survived and from that root most European varieties were grown. Dahlia flowers are the perfect cut flower for home use.
Dahlia tubers prefer a sandy, well draining soil with a pH between 6.2 and 6.5. Sand can be added to clay soil to help the plant thrive.
Cut dahlia flowers can last for up to a week indoors in a flower arrangement. By growing a variety of different dahlias, an entire arrangement can be made from dahlia flowers alone and provide both large and small flowers for stunning results.
Choosing a Variety
Dahlia plants should be chosen based on their intended use in the garden. Low growing plants can be used in borders or along walkways, while the taller dahlias can be used for shading, background flowers or stunning centerpieces.
Wait until all danger of frost has passed and plant dahlias in soil that is at least 60 degrees. It is best not to plant dahlias during the rainy time of spring as this can cause the tubers to rot. Dig holes a foot deep and a foot wide and fill to a depth of 6 inches with compost or other organic soil mixes. Lay the tuber in the hole with the eye pointing upward. Pound in a stake beside the tuber if planting a tall variety of dahlia. Cover the dahlia tuber with approximately 2 inches of soil. When the sprouts begin to appear, fill the hole an inch at a time until the hole is completely filled. Use old pantyhose lengths or ripped sheeting to tie the plant to the stakes as necessary.
Water weekly until dahlias are well established. During hot, dry periods, the dahlia should be watered twice or more a week if necessary. In order to produce large blooms, select a few buds to grow and remove any remaining buds. To keep the dahlia blooming continuously during the growing season, remove spent buds immediately.If the dahlias are planted in USDA Zones 8 to 10, dahlia tubers can be left in the ground over winter. Other zones should dig the tubers in the fall before the first freeze. Divide the tubers making sure each has an eye for the next year's growth. Store the tubers in a dry area that is not subject to freezing. Check the tubers several times over the winter for mold and shriveling.