15 Types of Dahlias

With so many types of dahlias, it can be challenging to figure out which ones to choose. What will you be growing next?

Known for their stunning blooms, it’s no wonder dahlias are found in so many gardens worldwide. Are you aware there are more than 57,000 different dahlia cultivars?

With so many types choose from, it’s easy to get confused and overwhelmed. To help clear up confusion, let’s talk about the different types and what sets them apart.

How Can There Be So Many Different Species?

The dahlia genus consists of 42 different species, which isn’t many compared to roses with 150. How can a smaller genera have so many more hybrids or cultivars? The 57,000 registered types are possible because dahlias have eight homologous chromosomes for genetic mixing, unlike most other plants with only two sets.

Organizing Cultivars Into Groups

To help organize the thousands of different dahlias types, a grouping system is often used based on the flowers’ characteristics. It imposes some order but isn’t straightforward. International approaches vary in their groupings, and the groups contain sub-divisions, which results in slightly different systems used by other societies or associations. This lack of uniformity creates some confusion.

In an attempt to organize the massive number of cultivars, numerous associations have arranged them by flower characteristics. But even this isn’t very clear because international approaches are different, and there are sub-divisions within the groups. 

Flower Characteristics Used For Grouping

Before we delve into the different groupings, let’s talk about a dahlia’s flowers parts and how they are used to classify them. 

Dahlias belong to the Asteraceae family, consisting of highly-evolved plants with composite flowers. Many people are unaware that composite flowers are smaller, simple flowers called florets. There are two different florets: the disc florets and ray florets.

  • Disc florets are at the flower’s center. They are typically small, tubular structures packed into tight spiral patterns. This type of floret has reproductive parts, including pollen, and is often yellow to draw in pollinators.
  • Ray florets are the parts we usually call petals. They are showy, colored structures that surround the disc florets. Ray florets are sterile, so they don’t have evident reproductive parts. To help further describe ray florets, they can be involute where the edges fold up or revolute where the edges fold down.
Thousands of blooming yellow flowers

15 Official Dahlia Divisions

The UK’s National Dahlia Society (NDS) Classification is one of the most commonly recognized systems worldwide. It organizes dahlia types into fifteen different groups or divisions, with a couple of groups containing subdivisions for flower sizes. Since it is recognized worldwide and one of the most commonly used systems, we will focus on the NDS classification hierarchy for this article.

Bloom Size Subdivisions

  • Giant flowers (>10 inches in diameter)
  • Large flowers (8 to 10 inches in diameter)
  • Medium flowers (6 to 8 inches in diameter)
  • Small flowers (4 to 6 inches in diameter)
  • Miniature flowers (<4 inches in diameter)

Group 1: Single-flowered

Single-flowered dahlias are one of the best for bees and other pollinators. These flowers have flat ray florets arranged in a single ring that often overlap slightly. The ray florets may also have contrasting colors towards the bottom or center of the dahlia. Disc florets form a tight, central disk and are easy to access with a single ring of ray florets. 

Recommended Garden Varieties

  • Hadrian’s Sunset
  • Happy Single Romeo
  • Happy Single Princess
  • Magenta Star
  • Moonfire
  • Sunshine

Group 2: Anemone-flowered

Anemone flowered types don’t have a visible disc in the center. One ring or numerous rights of flat ray florets surround a dense central cluster of tubular disc florets. The flowers almost look like a small carnation set on a daisy’s petals. Sometimes the ray and disc florets are the same color, but they are typically different.

Recommended Garden Varieties

  • Alpen Fury
  • Blue Bayou
  • Garden Show
  • Lifestyle
  • Ryecroft Jim
  • The Phantom
  • Que Sera
Blooming purple dahlia in the garden

Group 3: Collerette

Collerette dahlia varieties have a distinct outer ring of eight or more flat ray florets and a center ring of disc florets. But the unique aspect of this group is the inner ring of smaller ray florets known as “the collar.” The collar is often a different color than the ray florets and symmetrical. 

Recommended Garden Varieties

  • Bumble Rumble
  • Christmas Carol
  • Clair de Lune
  • Impression Fabula
  • Kelsey Annie Joy
  • Olivia
A small butterfly on a purple dahlia flower

Group 4: Waterlily

Waterlily dahlias have broad, somewhat scant, wide ray florets that form fully double blooms. The ray florets are straight or slightly involute, giving the flower head a shallow look or saucer shape. Waterlily types also have a firm yet closed center of disc florets. Overall, the flower depth is no more than one-third of the bloom’s diameter.

Recommended Garden Varieties

  • Anna Lindh
  • Creme de Cassis 
  • Karma Choc
  • Nepos
  • Porcelain
  • Rancho
  • Swan Island
A blooming pink dahlia in the garden

Group 5: Formal Decorative

Decorative types are similar to ball dahlias, with fully double blooms and involute rays, but they don’t have a visible center disc. They have many ray florets, but they are typically involute along up to 75% of their length, so they are more twisted or turned inward. The tips are usually bluntly pointed.

Formal decorative dahlias are categorized into subdivisions based on their bloom size.

Recommended Garden Varieties

  • Andrea Lawson (Miniature Flower)
  • Barbary Sultan (Small Flower)
  • Cafe au Lait (Large Flower)
  • Edinburg (Small Flower)
  • Hamari Gold (Giant Flower)
  • Hillcrest Firecrest (Small Flower)
  • Mystique (Medium Flower)
  • Lavender Perfection (Giant Flower)
  • Oreti Classic (Medium Flower)
  • Ryecroft Rebel (Large Flower)
A closeup picture of a beautiful pink dahlia

Group 6: Ball

Ball dahlias are quite similar to the formal decorative types. They have fully double, ball-shaped, or slightly flattened blooms without a visible center disc. The ray florets have rounded tips and involute for more than 75% of the rays’ edge. Ray florets are also semi-tubular and spirally arranged around the blooms. 

Recommended Garden Varieties

  • Amy Cave (Small Ball)
  • Aurora’s Kiss (Miniature Ball)
  • Boom Boom Red (Giant Ball)
  • Downham Royal (Miniature Ball)
  • Jowey Winnie (Small Ball)
  • Marble Ball (Small Ball) 
  • Ruskin Tangerine (Miniature Ball)
Beautiful and blooming peachy pink dahlia

Group 7: Pompon

Pompon dahlias are smaller than ball types and almost round in shape. Blooms are fully double with tubular ray florets with blunted tips. They display a stunning swirl of florets—without a visible center disk. Pompon types are popular as cut flowers and in arrangements.

Recommended Garden Varieties

  • Amgard Beacon (Large Pompon)
  • Bowen (Miniature Pompon)
  • Franz Kafka (Large Pompon)
  • Johann (Miniature )Pompon)
  • Martin’s Yellow (Miniature Pompon)
  • Ms Kennedy (Miniature Pompon)
  • Pensford Marion (Miniature Pompon)
  • Wizard of Oz (Miniature Pompon)
A dark pink pompon flower under the heat of the sun

Group 8: Cactus

Cactus varieties usually have fully double blooms with pointed or spiky narrow raw florets. These ray florets revolute for more than 65% of their length, giving flowers a star-like appearance. The florets curve inwards on some cactus dahlia varieties, and others stand straight out from the stem. 

Recommended Garden Varieties

  • Clearview Sharron (Medium Cactus)
  • Deborah’s Kiwi (Small Cactus)
  • Good Earth (Medium Cactus)
  • Gracie S (Miniature Cactus)
  • Karras 150 (Small Cactus)
  • Sure Thing (Medium Cactus)
  • Weston Pirate (Miniature Cactus)
A pink good earth cactus dahlia flower

Group 9: Semi-Cactus

Semi-cactus cultivars have fully double blooms like cactus dahlia types, but the semi-cactus have broader ray florets, and they revolute or roll back for about half the length. Ray florets are typically pointed; they revolute between 25 and 65% of their length. Blooms look spiky, but this unique curvature means they are more tolerant of bad weather.

Recommended Garden Varieties

  • Aitara Majesty (Giant Semi-Cactus)
  • Aloha (Medium Semi-Cactus)
  • Avoca Comanche (Small Semi-Cactus)
  • Badger Twinkle (Miniature Semi-Cactus)
  • Black Jack (Large Semi-Cactus)
  • Candy Keene (Large Semi-Cactus)
  • Embrace (Small Semi-Cactus)
  • Match (Small Semi-Cactus)
  • Ruskin Andrea (Small Semi-Cactus)
  • Shandy (Small Semi-Cactus)
  • Tui Avis (Miniature Semi- Cactus)
  • Veritable (Medium Semi-Cactus)
  • Weston Stardust (Miniature Semi-Cactus) 
A red and yellow semi-cactus dahlia

Group 10: Miscellaneous

This group covers all varieties that don’t fall within the other groups. The miscellaneous group also includes the original dahlia species. Once enough similar types are collected in the miscellaneous category, a new group is formed for them. Paeony and stellar dahlias were included in this group until recently. 

Recommended Garden Varieties

  • Akita
  • Dahlia Coccinea
  • Dahlia Pinnate
  • Jewel Orange
  • Lorona Dawn
  • Samantha
  • Vancouver
Beautiful red akita dahlia flower in the garden

Group 11: Fimbriated

Fimbriated dahlias display a ruffled or fringed look because the ray florets’ tips are split or notched into uniform sections. The rays come in many different shapes. They can be flat, involute, revolute, twisted, or incurving. Fimbriated dahlia types don’t have a definitive center disk. Blooms often come in multiple colors or stripes. 

Recommended Garden Varieties

  • Apache
  • Jean Ellen
  • Kenora Frills
  • Marlene Joy
  • Mel’s Orange Marmalade
A pink fimbriated dahlia blooming in the garden

Group 12: Star

Star varieties have blossoms with a single outer ring of ray florets circling a distinctive central ring of disc florets. Depending on the exact type, all ray florets are either revolute or involute. Since the ray florets do not overlap and completely turn inward or outward, creating a unique star-shaped bloom. This group was previously known as the single orchid dahlias.

Recommended Garden Varieties

  • Destiny’s Reacher
  • Hillcrest
  • Honka
  • Honka Surprise
  • Midnight Star
  • Sophie Taylor
  • Tahoma Star
  • Veronne’s Obsidian
A reddish purple dahlia blooming in the garden

Group 13: Double Orchid

Double orchid cultivars have one of the most unique flower forms (and colorations) amongst the dahlia groups. Fully double blooms have no visible disc but triangular centers of tightly closed florets. The lance-shaped ray florets are long and narrow and can be either revolute or involute. Double orchid blooms come in multicolors, beautifully mottled patterns, or solid hues.

Recommended Garden Varieties

  • Gallery Art Deco
  • Gallery Art Nouveau
  • Giraffe
  • Jescot Julie
  • Pink Giraffe
  • Tohsuikyoh
A pink orchid dahlia blooming with green leaves in the background

Group 14: Peony (Paeony)

Peony flowered dahlia varieties have more than one ring of ray florets surrounding a central clump of disc florets. The ray florets are usually slightly involute at their base but then flatten out along the length or are gently revolute. Like single-flowered dahlias, the disc florets’ reproductive parts (and pollen) are apparent.

Recommended Garden Varieties

  • Bishop of Auckland
  • Bishop of Canterbury
  • Bishop of Leicester
  • Bishop of Llandaf
  • Bishop of York
  • Classic Rosamunde
A bright pink dahlia blooming in the garden against dark green leaves

Group 15: Stellar

Stellar varieties are an interesting mix of flower characteristics. The double blooms don’t have a disk, and the narrow pointy ray florets resemble those on the star dahlias. But they demonstrate the uniform arrangement and shape similar to the ball or formal decorative varieties. Individual ray florets recurve towards the stem, with partially involute edges.

Recommended Garden Varieties

  • Alloway Candy
  • Camano Pet
  • Diane Brazil
  • Gitts Crazy
  • Irish Blackhart
  • Seabeck’s Hilda
A beautiful pink stellar dahlia blooming under the sun
Carley Miller
Carley Miller is a horticultural expert at Bustling Nest. She previously owned a landscaping business for 25 years and worked at a local garden center for 10 years.
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