Long-Blooming Dahlias and Tuberous Begonias: A Summer Showstopper Duo

Long-Blooming Dahlias and Tuberous Begonias: A Summer Showstopper Duo

Dahlias and tuberous begonias share a surprising number of traits, making them natural partners in the summer garden. Both grow from tubers that can be started indoors in pots for a head start before transplanting outside once frost danger has passed. They thrive in rich, well-drained soil with consistent moisture, and neither is cold-hardy—but their tubers store easily over winter. Simply dig them up in fall and keep them in a cool, dry place until spring.

For visual guidance, watch our videos "How to Grow Tuberous Begonias" and "Dividing Dahlias," or consult our Growing Guides by Plant Name for complete instructions.

Bloom Time and Flower Power

Both plants begin flowering in July, though some varieties start later, and they keep blooming until late season when most perennials have faded. Dahlias and begonias produce rounded blossoms in a wide spectrum of colors. Dahlias are legendary as cut flowers—long, sturdy stems and blooms that last a week or more in a vase. Cutting actually encourages more flowers. Begonia blooms are more delicate but look lovely floating in a bowl of water.

Key Differences

• Fragrance: Some begonias (e.g., 'John Smith' and Scentiment® Blush) offer a fresh citrus scent, while most dahlias are fragrance-free.
• Height: Dahlias range from petite to statuesque; upright tuberous begonias top out around 2 feet, and trailing types excel in hanging baskets.
• Flower size: Begonia blooms span 2–6 inches; dinnerplate dahlias can reach the size of a dinner plate.
• Sun needs: Dahlias prefer full to part sun; begonias thrive in part sun to full shade.
• Propagation: Dahlia tubers multiply quickly, while begonia tubers propagate slowly, making them pricier.

Container Versatility

Both begonias and compact dahlias (such as the Melody series) flourish in containers, adding flexibility to your designs. Taller dahlias (over 24 inches) benefit from staking—especially large-flowered garden types like those in our Dinnerplate Collection. Drive stakes carefully to avoid damaging the tuber.

Design Ideas

Use dahlias as filler plants in the middle of borders, planting in groups of three or six. For a lavish display, mass them using collections like Shades of Pink or the Karma Dahlia Collection.