Dahlia types and sizes

Dahlia types and sizes

The world of dahlias can be intimidating when you first start learning about these beautiful flowers. There are so many different types and classifications.

Here is some information that you might find useful on your journey to growing dahlias. Dahlia petals are called 'florets' and it's how the florets are formed which determines how a bloom is classified. I have used the word petals in this summary to make it more accessible to everyone. 

Dahlia types:

Pompon - the smallest of the dahlia types that are about the size of a golf ball. Adorable little round flowers with petals going all the way back to the stem. Petal tips should appear rounded.

Pictured below: Glenbank Honeycomb

Ball -  exactly how it sounds. Round, ball shaped blooms with lots of petals which go all the way back to the stem.  Petals curl in on themselves forming a tube at the base. These are the longest lasting as a cut flower due to their high petal count and firm shape which is not easily damaged during transport.

Pictured below: Salmon Joy

Decorative - these dahlias have a high petal count with a closed center however the flowers are flatter than a ball form (not as deep). Their form varies a lot as this classification fills the gap between the ball form and the cactus form.

A formal decorative has petals which are flat, neatly arranged and usually have a rounded petal tip. 

Pictured below: Florelie Magpie

An informal decorative has petals which are usually curved or wavy with a pointed petal tip.

Pictured below: Carlos Watermelon

There are many other types of dahlias including singles, collerettes, orchid, orchette, anemones, cactus, stellar, waterlily and laciniated /fimbriated. We have focused on the types most commonly used for commercial cut flowers in this post although all dahlias can be used as cut flowers.

For more detailed information about dahlia types visit the Dahlia Society of Victoria website (https://dahliasocietyofvictoria.org.au/Dahlias-for-showing). Information on judging dahlias and the Australian point scoring system used in competitions can also be found there.

We often like to classify and organise things however plants don't always neatly fit into a category so think of these types a bit like a continuum with flowers falling along the spectrum.

Dahlia Sizes:

Dahlias are classified into size groups which are used in dahlia showing competitions.

Pompon - less than 50mm 

Miniature - under 120mm

Small - between 120mm - 160mm

Medium - between 160mm - 210mm

Large -between 210mm - 260mm

Giant - above 260mm

The term 'dinnerplate' is often used to refer to big dahlias. This isn't a formal classification but is often used to refer to dahlias that are large or giant in size.

As a cut flower farm we predominantly grow miniature and small sized blooms on the farm with a smaller number of pompons and medium sized blooms. Even dahlias in the 'small category' are quite large compared to other flowers commonly used in floral arrangements. Typically as the flower size increases the vase life decreases. 

My sincere thanks to Debra Collett from the Dahlia Society of Victoria for cross checking my information.

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Would like to place an order but not good on the email stuff would it be possible to call to discuss and any questions that I have please

Anna maiolo

We have a section at our local show for Exhibition Cactus which I think is a Incurved cactus, like winkie paddlewheel.
Just wondering if you know of anyone that may have this type of tuber?
I live near Armidale NSW,
the dahlia section at the show was once very competitive. It would be nice if I could enter something in this section, before it’s lost forever.
Kind Regards,
Bridgett Hone

Bridgett Hone

Glad someoneis trying to help us beginners . Thanks Cliff

Clifford Parkinson

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