Few flowers offer as much variety as the dahlia. Bred into thousands of named varieties, dahlias are officially classified by the shape and arrangement of their petals into more than a dozen flower forms, from tiny pompons to plate-sized giants. Here are the main types of dahlias every gardener should know.
How dahlias are classified
Dahlias are grouped by flower form — the shape of the bloom and how its petals are arranged — and by size, from mignon (under 2 inches) up to “dinnerplate” giants over 10 inches across. Almost all grow from tubers planted in spring and flower from midsummer until frost.
The main types of dahlias
Here are the main dahlia flower forms.
Single Dahlias
Single dahlias have one row of petals around an open central disc, giving a simple, daisy-like look. Their open centers make them especially good for bees and other pollinators.
Anemone Dahlias
Anemone-flowered dahlias have one or more rings of flat outer petals surrounding a dense cushion of short, tubular florets in the center, creating a pincushion effect.
Collarette Dahlias
Collarettes have a single outer ring of broad petals with a “collar” of shorter, often contrasting petals around the central disc — a charming two-tone look loved by pollinators.
Waterlily Dahlias
Waterlily dahlias have broad, slightly cupped petals that form a shallow, elegant bloom resembling a waterlily. They’re a favorite for cutting thanks to their graceful shape.
Decorative Dahlias
Decoratives are fully double with broad, flat or slightly twisted petals and no visible center. They’re among the most popular garden and cut-flower dahlias and include many large varieties.
Ball Dahlias
Ball dahlias form neat, round blooms made of tightly rolled petals arranged in a spiral. Compact and long-lasting, they’re excellent for arrangements.
Pompon Dahlias
Pompons are like miniature ball dahlias, forming small, perfectly round flowers usually under two inches. They’re prolific and wonderful for cutting.
Cactus Dahlias
Cactus dahlias have narrow, pointed petals that roll backward and outward, giving a spiky, starburst appearance. They add dramatic texture to the border and vase.
Semi-Cactus Dahlias
Semi-cactus types sit between cactus and decorative forms, with petals that are broad at the base but roll and point toward the tips for a softer spiky look.
Peony-Flowered Dahlias
Peony-flowered dahlias have two or three rows of petals around an open center, giving a full but airy bloom that resembles a peony.
Dinnerplate Dahlias
“Dinnerplate” isn’t a form but a size — the term for giant decorative or cactus dahlias with blooms 10 inches or more across. These showstoppers grow on tall plants and always need staking.
How to choose the right dahlia
Choose your dahlias by how you’ll use them. For sheer drama, grow dinnerplates; for cutting, ball, pompon and waterlily forms hold up beautifully; for pollinators, plant singles, collarettes and anemones with open centers; and for bold texture, add cactus types. Mixing forms and heights gives the longest, most varied display.
Caring for dahlias
All dahlias want full sun, rich well-drained soil and staking for taller types. Plant tubers after the last frost, pinch young plants for bushiness, feed a low-nitrogen fertilizer, and in cold climates lift and store the tubers over winter. See our dahlia growing and care guide.
Popular dahlias to grow
These famous named varieties show off the incredible range of dahlia forms:
- “Café au Lait” — the wildly popular blush dinnerplate wedding dahlia
- “Cornel” — a perfect deep-red ball dahlia, superb for cutting
- “Bishop of Llandaff” — scarlet single blooms over dark foliage
- “Karma Choc” — a dark-red cutting dahlia with long vase life
- “Sweet Nathalie” — a soft dusky-pink decorative favorite
- “Thomas Edison” — a rich royal-purple decorative dahlia
Dahlia colors
Dahlias come in nearly every color except true blue, from soft blush, peach and lavender to vivid red, orange, purple and near-black, plus countless bicolors and blends. With their huge range of forms and sizes on top of that color range, dahlias offer more variety than almost any other flower — which is exactly why cut-flower growers and gardeners collect them so passionately.
Dahlia types FAQs
What are the different types of dahlias?
Dahlias are classified by flower form, including single, anemone, collarette, waterlily, decorative, ball, pompon, cactus, semi-cactus and peony-flowered types, plus the giant “dinnerplate” size. Each has a distinct petal shape and arrangement.
What is a dinnerplate dahlia?
A dinnerplate dahlia is not a separate form but a size category — giant decorative or cactus dahlias with blooms 10 inches or more across. They grow on tall plants, make a dramatic statement, and always need staking to support their heavy flowers.
What is the difference between ball and pompon dahlias?
Both form round blooms from tightly rolled petals, but ball dahlias are larger (roughly 2 to 5 inches), while pompon dahlias are miniature, usually under two inches, and perfectly spherical. Both are excellent, long-lasting cut flowers.
Which dahlias are best for cut flowers?
Ball, pompon, waterlily and decorative dahlias are among the best for cutting because they have full, long-lasting blooms and strong stems. Picking regularly actually encourages the plants to produce even more flowers.
Which dahlias are best for pollinators?
Open-centered forms — single, collarette and anemone dahlias — are best for bees and other pollinators because their accessible centers provide easy nectar and pollen, unlike the fully double forms.
How many types of dahlias are there?
There are more than a dozen official dahlia flower forms and around 40 species, but breeders have produced tens of thousands of named varieties in nearly every color except true blue.
See the dahlia flower profile, the dahlia growing guide, and the national flower of Mexico.