Facts and myths behind the fabulous fall blooms.
dahlia facts
Credit: Alison Miksch

If you don't know what you're doing, growing your own dahlias can be tough. Here's some common misconceptions about the finnicky (yet fabulous!) fall flower.

1. Dahlias aren't native to the South

They're native to Mexico, but we'll claim ‘em, anyway. Although they naturally prefer higher elevation and cooler temperatures than the South can offer, with proper selection and mulching, they will succeed beautifully down here.

2. Dahlias grow from tubers, not bulbs

Although they look similar, tubers aren't hardy (enduring) like bulbs. They will freeze if the ground freezes, so if you live in an area that routinely experiences hard freezes, you need to pull and store the bulbs in sawdust for the winter.

3. Their tubers are edible

Dahlias were originally grown for nutritional purposes, not for their beauty. Apparently, dahlia tubers taste like across between carrots, celery, and potatoes, and are quite bland.

4. Dahlias are extremely varied in size

Not all are the 10-inch-wide "dinnerplate dahlias" of which our dreams are made. Miniature dahlais grow only a few inches tall; but those dreamy dinnerplates can grow up to 5 feet tall with 10-inch-wide flower blooms. No matter what size you'd like, there's truly a dahlia bloom for every taste.

5. For bigger tubers next year, feed more this year

The more food dahlias get, the more root mass they'll grow. The more roots, the more leaves, flowers, and tuber growth you'll have for next summer. Tubers re-planted or newly planted in enriched soil don't need additional food. If your soil is light, or if the tubers stayed in the ground the previous year, add compost or low-nitrogen fertilizer as food.

6. They're (slightly) temperamental

One of the best parts of growing your own dahlias is picking, arranging, and gifting them. To make the beautiful blooms last, pick nearly mature flowers in early morning or evening, immediately place cut stems in 2-3 inches of hot water and let stand, gradually cooling.

7. But don’t be too intimidated to grow dahlias yourself.

If you’re growing from tubers, wait until after the threat of the last frost has passed and the soil is warm to start planting. Tip: About a month before planting, amend the soil with organic matter so it will be nutrient-rich. Dig about a 1-foot-deep hole for planting tubers; space holes 4 to 5 feet apart to give the roots plenty of room to grow. Water regularly to a foot deep when the shoots are above ground, and keep watering throughout the season. If the ground in your zone freezes during winter, dig up tuberous roots in fall and store until next spring. If winter temperatures stay above 20°F in your zone and the soil has great drainage, dahlias can stay planted throughout the year.

8. There is no such thing as a black dahlia

The name "Black Dahlia" originated from an unsolved Hollywood murder mystery. But, no matter how many people try to create this mythical plant, the color black does not exist in the world of flowers. We prefer our dahlias bright and colorful, thank you very much!