Did you know that dahlias come in at least 18 forms (plus micro sizes of almost all these forms)?
Here are some of the most common forms:
Informal decoratives (like Belle of Barmera) are lush and romantic, the pillowy stars of the dahlia show.

Anemones have ray petals that can stream back like a comet and a pouffe of central florets (like Bloomquist Golden).

Ball forms have recurved petals that open evenly to form a globe (see AC White Rabbit).

Cactus forms aka “Straight cactus” (like Bloomquist Lace) are spiky with uniform petal distribution.

Incurved cactus forms (like Camano Sitka) and Semi cactus forms (like Bloomquist Karen G) have varying degrees of spikiness and twistiness, often winning popular opinion polls as the most unusual or interesting dahlias.


Collarette form dahlias (like Apple Blossom) are to many people the “sweetest” forms, with open centers surrounded by petaloid and simple, symmetrical ray petals.

Formal Decorative form dahlias (like A la Mode) are very uniform in shape, although they can have amazing color variation within their tidy petals! They do slightly recurve (especially as blooms mature), but they are more flat than ball forms.

Laciniated forms (like Vista Char) are fluffy, shaggy, fringed, and fuzzy. Their notched tips add a special beauty to the garden.

Novelty Fully Double (like Bloomquist Pincushion) and Novelty Open forms (like this beautiful TWF seedling from 2021!) don’t fit well into any other category, but they’re so beautiful that even form-focused dahlia judges can’t bear to exclude them!


Stellar forms (like Irish Pinwheel or Bloomquist Barb) are star-like as their name suggests, and have longer, uniform (often pointed) petals with a bit of space between.

Orchette forms (like Verrone’s Morning Star) are also star-shaped, with amazing quilled petals that roll into a point at the tips. They have a small cluster of ruffled petaloids at the center of each petal. [I should also mention the gorgeous Orchid form dahlia here (like Bloomquist French, Verrone’s Ele, or Honka), which is very similar to Orchette form dahlias but do not contain any petaloids.]


Single dahlias have open centers and a single row of petals (like Bloomquist Dainty). These are pollinator favorites!

Waterlily form dahlias (like Silver Years) resemble a classic pond waterlily, with layers of uniform petals and a flat back.

There are even more forms, including Mignon, Mini Ball, Peony-formed…
How many forms were you familiar with? Which is your favorite category? Let us know in the comments!
Bonus: Here is a reel we made for Instagram with all of the different forms.
Want to learn more about growing dahlias?
The Garden is a positive online membership community offered by Triple Wren Farms. Membership includes:
- First access to TWF tuber and seed sales
- A wealth of flower garden How-To topics
- Frequent seasonal Live Trainings and Q&A’s
- Our “Anyone Can Grow Dahlias” e-course
- Personalized gardening advice
- Encouraging gardening community and more…


