Long-blooming Dahlias and Tuberous Begonias

Long-blooming Dahlias and Tuberous Begonias share many traits. Both emerge from tubers, which can be started in pots indoors to give them a head start before going outdoors after the danger of frost has passed. They prefer well-drained, rich soil and even moisture. Neither are cold hardy, but their tubers can be stored over winter. Just dig them up in fall and protect them in a cool place. Click here to watch our videos, "How to Grow Tuberous Begonias," and "Dividing Dahlias." You'll also find complete instructions for each in our Growing Guides by Plant Name.

The bloom season for both Dahlias and Begonias begins in July, although for some varieties the show starts later. Usually flowering continues until late in the season, when most perennials have faded. Both Dahlia and Begonias produce rounded blooms in many different colors. Dahlias are legendary as cut flowers. Most have long, strong stems and the blossoms last up to a week or longer in a vase. Plants respond well to cutting, and bloom even more. While Begonia flowers are more delicate, they look lovely floating in a bowl of water.

There are also significant differences. Some Begonias have a fresh citrus-like scent ('John Smith' and Scentiment® Blush, for example) while most Dahlias have no fragrance. The heights of Dahlias vary dramatically, from petite to statuesque. Upright Tuberous Begonias top out around 2′, and the trailing types are ideal for hanging baskets. Begonia flower sizes range from 2–6″ in diameter, while some Dahlia blooms grow as big as dinner plates. Dahlias like full to part sun while Begonias prefer part sun to full shade. Dahlia tubers multiply rapidly, but Begonia tubers are slow to propagate, and thus more expensive. Begonias and compact Dahlias, such as the Melody varieties, thrive in containers. This gives them even more versatility. Dahlias that grow taller than 24″ will benefit from being staked. This is especially true for garden varieties with large flowers, such as those in our Dinnerplate Collection. Take care when pushing the stake into the soil to avoid injuring the tuber.Dahlias make great filler plants in middle of borders, planted in 3s or 6s. Or, to create an extravagant show, plant Dahlias in a mass, using multiples of Our Shades of Pink Collection or the Karma Dahlia Collection.