Dahlia Magic: How to Grow Show-Stopping Blooms
Dahlias are showstoppers in the summer and fall garden, prized for their bold colors, dramatic forms, and long bloom season. With proper planting and care, these tuberous perennials reward you with armloads of flowers from midsummer until the first frost. Whether you’re growing dinner-plate dahlias or petite pompons, success starts with thoughtful preparation and consistent care. Start planning now for a little dahlia magic in your garden when warmer breezes blow. Tubers are readily available for purchase.
Choose the Right Location
Dahlias thrive in full sun, requiring at least six to eight hours of direct sunlight each day. Select a location with well-draining soil, as soggy conditions can cause tubers to rot. If your soil is heavy clay, amend it with compost or plant dahlias in raised beds to improve drainage. Dahlias also appreciate good air circulation, which helps prevent disease.
When and How to Plant Dahlias
Plant dahlia tubers after the danger of frost has passed and soil temperatures reach about 60°F. In most regions, this falls between late spring and early summer. Dig a hole 6–8 inches deep and lay the tuber horizontally with the eye (the small growth nub) facing upward. Cover gently with soil but avoid watering heavily until shoots emerge, as excess moisture early on can cause rot.
Space plants according to their mature size—typically 18 to 24 inches apart for smaller varieties and up to 3 feet for larger types. Tall dahlias benefit from staking at planting time to avoid damaging tubers later.
Watering and Feeding
Once growth is established, dahlias need consistent moisture, especially during hot weather. Water deeply two to three times per week, allowing the soil to dry slightly between waterings. Avoid overhead watering to reduce the risk of fungal disease.
Dahlias are moderate feeders. Apply a low-nitrogen fertilizer once plants are about a foot tall and continue every three to four weeks. Too much nitrogen encourages leafy growth at the expense of blooms.
Maintenance for Dahlia Magic
Pinching young plants when they reach 12–16 inches tall promotes bushier growth and more flowers. Regular deadheading, removing spent blooms, keeps plants tidy and encourages continuous flowering. Likewise, when you cut a healthy flower, you’re essentially telling the plant to redirect its energy into producing new buds instead of putting resources into seed formation. This is the same principle as deadheading, just with a vase of flowers as the bonus. So cut away, create floral arrangements for indoor use, and enjoy more prolific blooms outside.
Photo by Christopher Lowe
End-of-Season Care
In colder climates, dahlias are not winter-hardy. After the first frost blackens the foliage, cut plants back to a few inches and carefully dig up the tubers. Allow them to dry, then store in a cool, dark place packed in peat moss or sawdust until spring. In warmer regions, tubers can often be left in the ground with a thick layer of mulch.
Garden Favorites
Here’s a collection of favorite types of dahlias. Order tubers online now so you’ll be ready for spring planting!
1. ‘Garden Time’
2. ‘Creme de Cassis’
3. ‘Topmix Red’
4. ‘Cornel Brons’
5. ‘Skyfall’
3. ‘Firepot’
A Garden Favorite Worth the Effort
With their extraordinary variety and extended bloom time, dahlias are a rewarding addition to any garden. A little attention to planting, watering, and maintenance goes a long way, ensuring these vibrant flowers take center stage from summer through fall, always creating a bit of dahlia magic.
