2019 is the Year of the Dahlia. These flamboyant, colorful plants yield gorgeous blooms from midsummer through autumn, when many plants are best their best. In colder zones, you’ll need to dig up and store the tubers before the first hard frost if you wish to grow them as perennials. Here’s how to plant, grow, harvest and store dahlias.
The National Garden Bureau has selected the beautiful dahlia as the bulb of the year.
Dahlia is a genus of tuberous plants that are members of the Asteraceae family; related species include the sunflower, daisy, chrysanthemum, and zinnia. They grow from small, brown, biennial tubers planted in the spring.
Picking a favorite dahlia is like going through a button box. As well as coming in a rainbow of colors, dahlia flowers can range in size from petite 2-inch lollipop-style pompoms to giant 15-inch “dinner plate” blooms. Most varieties grow 4 to 5 feet tall.
They are considered a tender perennial in cold regions North America. They are only winter hardy in planting zones 8 to 11. Gardeners in zones 2 to 7 can simply plant dahlia tubers in the spring and either treat them as annuals or dig them up and store for winter.
Dahlias love moist, moderate climates. Though not well suited to extremely hot climates (southern Florida or Texas), dahlias brighten up any sunny garden with a growing season that’s at least 120 days long.