The many types of dahlia flowers are hard to beat when it comes to the diversity of colors, sizes, and shapes in the garden. The blossoms of these easy-to-grow flowers come in what feels like an infinite range, from deep crimson red to snowy white, creamy pink to sunshine yellow, royal purple to barely black, with many colors in between. But dahlia diversity is more than color; these popular perennials grow in various shapes. From fluffy pompoms to orchid-like single flowers to massive dinner-plate blooms, the decorative dahlia adds a true rainbow of shapes, sizes, and colors to your garden. Read on to learn more about the many official types of dahlia flowers.
Official Types of Dahlias Explained
The America Dahlia Society (ADS) categorizes dahlias by size, color, and form. Flower sizes vary greatly, ranging from AA (10 inches in diameter or more) to MS (2 inches or less in diameter).
The ADS color categories include white, yellow, orange, pink, dark pink, red, lavender, purple and black, light blend (mix of the softer pastels), bronze, flame, dark blend, variegated (two or more colors in dots, splashes or stripes), and bi-color (two colors with distinct separation).
Finally, the ADS also designates 20 different forms. Let’s take a look at some of the most popular dahlia varieties you can grow in your own garden.
Formal decorative dahlias are named for their evenly spaced and regularly placed petals, also known as “ray florets.” The petals are double and dense, with a tendency to have a slight curve back toward the flower’s stem. The petal edges may roll slightly forward (partially involute) or slightly backward (partially revolute).
Popular types of formal decorative dahlias include:
- ‘Eveline’ has snowy white flowers with a lavender margin and a blooming season that lasts from July through frost.
- ‘Hillcrest Firecrest’ has medium-sized, bi-color yellow and red flowers.
- ‘Kelvin Floodlight’: A dinner plate dahlia with lemony blooms and slightly pointed petals.
- ‘Rothesay Reveller’: A medium-sized flower that grows to 3 feet tall with purple and white petals.
- ‘Barbarry Sultan’ has small flowers with dark pink to red petals.
Informal decorative dahlias look a lot like formal decorative, but their petals aren’t evenly and regularly spaced. Petals may be flat, twisted, curled, wavy, and partially revolute. The ray florets’ irregular spacing gives them an informal look.
Popular varieties of informal decorative dahlias include:
- ‘Cafe au Lait’: A wildly popular and photogenic dinner plate dahlia with stunning, 10-inch flowers in creamy blush, peach, or beige.
- ‘Crazy Love’ is a medium-sized dahlia with white petals around a yellow center, ray florets have a thin purple margin.
- ‘Gitt’s Perfection’ boasts enormous, pale pink flowers that fade to a white center atop 4-foot-tall stems.
- ‘Labyrinth’: A dinner plate dahlia with vibrant peach, pink and coral bi-color petals.
- ‘Thomas Edison’ informal decorative dahlias have 8-inch purple flowers that bloom profusely.
Semi-cactus dahlias are known for petals that are flat at their base, then revolute for less than half of their length. Petals may be straight, recurved, or incurved. Semi-cactus dahlias have double blooms.
Popular types of semi-cactus dahlias include:
- ‘Black Jack’ has a large, 8-inch flower with pointy, deep red ray florets around an almost-black heart.
- ‘Inca Dambuster’: A giant, yellow semi-cactus that reaches up to 10 inches in diameter.
- ‘Veritable’: Grows up to 44 inches tall with medium white flowers with dramatic purple tips.
- ‘Weston Stardust’ is an award-winning miniature semi-cactus with stunning red to yellow petals.
Petals are revolute for more than half their length, creating an almost “spiny” appearance. The ray florets may be straight, almost straight, pointed, or recurved. They emerge from the flower head in all directions. Because the petals are rolled, they don’t collect water; they weigh less and may not need staking.
Popular straight cactus dahlias include:
- ‘Bora Bora’: Bright pink petals that fade to yellow at the center.
- ‘Karma Sangria’ has salmon and yellow petals on a 6-inch bloom.
- ‘Mingus Randy’: A giant dinner plate variety that produces lavender and white flowers.
- ‘Tu Tu’ is a newer variety with spiky, double, pure white petals.
Like the straight cactus dahlia, the incurved cactus also has petals that roll for more than half their length. Most look completely rolled, from the base to their pointed tip. However, the petals also curve inward toward the center of the flower.
Popular incurved cactus dahlia varieties include:
- ‘Bed Head’ has small, 4-inch blooms in an eye-catching peachy coral hue.
- ‘Hey Mom’: Giant, 10-inch flower heads with snowy white petals.
- ‘Jungle Man’ stands up to 6 feet tall and has dark red, 7-inch flower heads.
- ‘Northlake Heritage’ has pale, lemon-yellow petals that make almost 90-degree turns for a unique look.
Laciniated dahlias are named for the split, or laciniation, found at the end of each petal. This gives them a frilly look, as though they were cut with pinking shears. The petals are uniformly arranged and may be involute or revolute.
Popular types of laciniate dahlias include:
- ‘Myrtle’s Folly’: These unusual dahlias have pink, yellow, and orange petals that are so narrow that they twist, making them look fluffy.
- ‘Northlake Pride’ has extremely narrow, bright red petals that create an eye-catching spiky appearance.
- ‘Omega’ is a dinner plate dahlia with pink and yellow petals that twist and twirl.
- ‘Urchin’ sports a deep red-to-purple hue and spiny-looking petals that resemble the sea creature it’s named after.
Not surprisingly, ball dahlias bloom in the shape of a sphere — though some varieties may have a slightly flattened face — and have fully double blossoms. Petals usually grow in a spiral pattern and may have blunt, indented, or rounded margins. Ray florets may be mostly involute for most of their length, or fully involute for half of their length.
Popular ball dahlia varieties include:
- ‘Amy Cave’: This dahlia has deep red-purple petals, ringed in concentric circles on a 6-inch flower head.
- ‘Bonanza’ boasts luscious raspberry and peach tones around a deep maroon center.
- ‘Cornel’ has 4-inch-wide flowers with lovely, cherry-red petals arranged in neatly spiraling circles.
- ‘Franz Kafka’: This award-winning dahlia offers 3-inch blooms in a dark pink honeycomb pattern that looks almost geometric in nature.
- ‘Wine Eyed Jill’ is a smaller plant with miniature ball flowers with tightly packed petals that range from palest pink to deepest burgundy at the heart.
Miniature ball dahlia also boasts sphere-like, fully double blossoms like the larger ball type. Petals can be indented, round, or blunt and may be partially or fully involute. They differ in size; miniature ball dahlias are smaller than their larger cousins.
Popular varieties of miniature ball dahlias include:
- ‘Aurora’s Kiss’ adds darkest red to the garden, with small round blooms atop tall stems.
- ‘Charlotte Bateson’: This miniature ball dahlia has rich pink petals, perfectly arranged in concentric circles
- ‘Downham Royal’ dahlias bloom in an unusual deep-pink and purple mix that makes the small flowers look almost iridescent.
- ‘Ruskin Tangerine’ brings the brightest orange, 2.5-inch flowers to the middle of the flower bed.
- ‘Ryecroft Yellow Orb’: 3-inch balls of sunshine yellow bloom from summer through fall.
Like ball dahlias, pompons have fully double flower heads. However, they’re even more globular in shape and smaller in size at only about 2 inches. Pompon petals may be partially involute for their entire length or fully involute for more than half their length.
Popular types of pompon dahlias include:
- ‘Gillwood Violet’: This variety brings a hint of purple and lavender to the garden bed with 2-inch spherical blossoms and dark foliage.
- ‘Martin’s Yellow’ has 2-inch bright yellow flowers that fade to lemon yellow at the margins atop 3-foot tall stems.
- ‘Ms Kennedy’ has larger flowers than many pompon varieties and offers brilliant orange-yellow tones with an almost-pink center.
- ‘Noreen’ has light pink petals that fade to almost white at the tips and a full, round appearance.
- ‘Pensford Marion’: This variety has small, deep red-pink flowers that bring the hue of raspberries to mind.
Stellar dahlias are fully double and characterized by gradating differences between immature and mature florets. Immature ray florets are narrow and partially involute, with maturing ray florets gradually growing more involute, all with a slight recurve toward the stem. Proportion is key, too, with an ideal depth being more than 2/3 to 1/2 that of the diameter.
Popular stellar dahlia varieties include:
- ‘Alloway Candy’ boasts baby-pink blooms, making them a favorite for wedding parties and baby showers.
- ‘Camano Pet’: This small, stellar dahlia has 4-inch flowers with buttery yellow petals and orange-pink margins.
- ‘Felida Stars and Stripes’ is a showy, bi-color dahlia with dramatic red and white petals.
- ‘Gitt’s Crazy’ sports large, 7-inch flowers in stunning shades of gold and fuchsia.
- ‘Irish Pinwheel’ has strongly recurved golden petals that deepen to a cherry red center.
Waterlily double blooms and symmetrical placement, waterlily dahlias look flat from the side. Four to seven rows of outer ray florets surround a closed, dome-shaped center. Petals are usually broad, flat, or slightly cupped and often incurved somewhat to a depth of about one-third of the flower’s diameter.
Popular types of waterlily dahlias include:
- ‘Creme de Cassis’ is a stunning variety with a deep burgundy center, surrounded by flat, broad light pink petals.
- ‘Firepot’ offers a bright burst of color, with unusual bicolor petals of sunny orange and fiery red-orange.
- ‘Gerrie Hoeck’: This popular dahlia is beloved for its tropical flowers, and dark pink hue.
- ‘Happy Butterfly’ waterlily dahlias have cheerful, buttery yellow petals streaked with striking burgundy.
- ‘Pearl of Heemstede’ has silver-pink, 8-inch flowers that contrast with its dark green foliage.
Unlike waterlily dahlias, peony dahlias have an open center and are single flowering. They also have two or more rings of petals around a disc of tiny, tube-shaped florets. Petals that grow around the disc are often curled, twisted, small, or otherwise irregularly shaped.
Popular peony dahlia varieties include:
- ‘Bishop of Canterbury’: Offers a splash of magenta flowers that bloom late in summer.
- ‘Bishop of Llandaf’ is a classic variety that boasts bright, cardinal red petals atop foliage so dark that it almost appears black.
- ‘Bishop of Oxford’ also has deep, dark foliage but is topped with cheerful coppery orange blossoms.
- ‘Fascination’: This peony dahlia is a semi-double variety with a bright pink hue and green-purple foliage.
- ‘Waltzing Mathilda’: An award winner with purple foliage and 4-inch flowers that range from red and orange to yellow and coral.
Anemone dahlias can be identified by rows of (usually flat) petals surrounding a densely petaled central disc. The disc is made of tightly packed, colorful, tubular petals that grow in a domed shape that resembles a pincushion.
Popular varieties of anemone dahlias include:
- ‘Boogie Woogie’ boasts a bright orange-yellow pincushion, ringed by happy pink and mauve outer petals.
- ‘Edge of Joy’: Slightly pointed, pale pink petals surround a deeper center for dramatic contrast.
- ‘Paso Doble’ sports a yellow center surrounded by white petals and resembles a sunny side-up egg or a spring daffodil.
- ‘Purple Haze’: A late-summer bloomer with bright magenta, 6-inch blossoms.
- ‘Totally Tangerine’: Bright orange flowers surround a pink pincushion, all atop a sturdy stem.
The collarette dahlia has a single row of flat or slightly cupped petals. A smaller ring of petaloids, less than half the length of the outer petals, rings the central disc.
Popular collarette dahlia types include:
- ‘Mary Evelyn’ adds drama to the garden with strongly contrasting rings of burgundy, white and yellow.
- ‘Night Butterfly’: Another striking cellarette, this dahlia boasts bright red outer petals around a ring of white streaked with pink.
- ‘Pooh’ is named for the beloved bear, with rings of bright yellow and orange hues.
- ‘Teesbroke Audrey’: Soft pastel pinks ring an inner layer of snowy petaloids around a central ring of sunny yellow.
- ‘Twyning’s White Chocolate’ offers luscious white blossoms around a creamy, fringed petaloid ring.
Single dahlias have a solitary row of petals surrounding a disc of tightly packed petaloids. This type of dahlia has ray florets that lie flat and are evenly spaced around the central disc. Petals may overlap, and colors often concentrate toward the center.
Popular varieties of single dahlias include:
- ‘Bright Eyes’ features vibrant magenta petals that surround bright yellow centers, with upright stamens that attract pollinators.
- ‘Hadrian’s Sunset’ is a compact variety with coral, bronze and orange flowers atop dark purple foliage.
- ‘Mexican Star’: Deep burgundy petals surround a golden yellow center, filling the air with rich fragrance.
- ‘Sunshine’: A small dahlia for the front of the border, with bright yellow-to-orange blossoms above fern-like foliage.
Mingon single dahlias have the same characteristics as single dahlias — a single row of petals surrounding a disc — but have smaller diameters. Mignon single flowers grow to a diameter of 2 inches or less.
Popular mignon single dahlia types include:
- ‘G. F. Hemerick’ dahlias produce coppery flowers with a yellow central disc from summer through fall.
- ‘Pulp Fiction’ has bright red flowers atop deep purple foliage and only reaches about a foot tall.
- ‘Scura’: Produces eye-catching tangerine flowers with deep orange centers; blossoms are only about in inch in diameter.
- ‘Sunshine’ has buttery golden petals that deepen to orange and dark, fernlike foliage.
Orchid dahlias feature one row (single) or two rows (double) of regularly spaced petals around a central disc. At least 2/3 of petal length is partially involute, and 1/3 of length is fully involute. Petals may overlap.
Popular types of orchid dahlias include:
- ‘Honka Fragile’ has a single row of white, almost completely rolled petals with a very fine red margin.
- ‘Honka Red’: This elegant dahlia has a single row of deeply involuted red petals, creating a star-shaped flower around a bright yellow central disc.
- ‘Jescot Julie’ boasts 6-inch orange flowers with a deeper, darker underside.
- ‘Pink Giraffe’: This award-winner has two rows of pale pink petals that involute to show their deep pink stippled undersides.
Orchette dahlias combine characteristics of orchid and collarettes. Like orchid dahlias, 2/3 of orchette petal length is partially involute, while 1/3 of the length is fully involute. Like collarettes, the orchette has a petaloid-ringed central disc.
Popular orchette dahlia varieties include:
- ‘Christmas Star’ has festive red petals that involute to show white undersides, around white petaloids.
- ‘Rae Ann’s Antares’: Boasts swirls of violet and white around a snowy ring of petaloids.
- ‘Rae Ann’s Volunteer’ looks like a white star, with a yellow disc framed by creamy ray florets or pure white.
- ‘Verone’s Ele’ catches the eye with deep pink petals around a buttery yellow central ring of ruffly petaloids.
- ‘Verone’s Morning Star’: Brightens the garden at dusk with pointed, starlike ray florets surrounding white petaloids.
Novelty open dahlias don’t fit neatly into any of the other ADS classifications. They may have different characteristics but can be identified by an open, visible central disc.
Popular types of novelty open dahlias include:
- ‘Apple Blossom’ is sought-after by wedding florists due to its soft, peachy blush tones that fade to buttery cream.
- ‘Dad’s Favorite’: Lovely purple petals with rounded edges surround huge, golden flecked central discs.
- ‘Hy Zizzle’ sports deep lavender ray florets and a puffy, frilly center in eye-catching gold and raspberry tones.
- ‘Rock Star’ is saturated with color, thanks to brilliant cranberry and purple petals.
Novelty Fully Double
As their name suggests, novelty fully double also doesn’t fit neatly into the other ADS form categories. However, these dahlias have a fully double center.
Popular novelty fully double varieties include:
- ‘Akita’ produces 8 to 10-inch flowers streaked with yellow, gold, bronze, and deep red.
- ‘Bloomquist Pincushion’: Luscious purple petals with a voluminous appearance.
- ‘Platinum Blonde’ have double white blooms surrounding a fuzzy, fluffy buttercream center.
- ‘Polka’: Rows of white petals streaked with cranberry ring the frilly yellow petaloid at the flower’s center.
With so many choices — almost 70,000, to be exact — dahlia varieties come in an almost infinite range of sizes, shapes, and colors. Most are relatively easy to grow, making dahlias a great choice for anyone who dreams of a rainbow of color in the garden.
For more, see our in-depth guide to cutting dahlia flowers for a vase or bouquet arrangement.