Dahlia classification

Classification codes are a means to group the many varieties of dahlias that exist

Cactus Types

IC: Incurved Cactus —Petals rolled for their full length, with tips of the petals curving toward the center of the flower.

SC: Semi Cactus — Petals flat at the base, with less than half of the petals, rolled or quilled.

C: Straight Cactus — Petals rolled for one-half their length, straight or nearly straight.

Decorative Types

FD: Formal Decorative — Flat petals with an even, regular placement throughout the flowers.

ID: Informal Decorative — Generally flat petals, sometimes slightly rolled at the tips, but with irregular arrangement of formation.

Balls and Pom Pons

BA: Ball — Fully double flowers, ball-shaped or slightly flattened at the face, the ray florets blunt, rounded, or indented. Involute for most of their length, fully involute for about one-half their length, and normally displayed in a spiral arrangement.

P: Pom Pon — Fully double flowers almost round in shape with tightly quilled petals. Flower size 2" or less.

Singles, Semi Doubles, Collarettes, and Anemones

S: Single — Single row of flat petals surrounding a disc.

SD: Semi-Double — Two or more rows of petals surrounding a disc.

CO: Collarette — One row of flat or slightly cupped petals surrounding a disc. These flowers have an inner set of petaloid generally multiple and irregular forming a collar around the disc.

AN: Anemone — One or more rows of petals surrounding a dense group of colored, elongated disc florets.

MS: Mignon Single — a single row of petals, with a flower diameter under 2".

Orchid & Peony

O: Orchid Type — Open-centered flowers with one of the ray florets surrounding a disc. The florets involute for two-thirds or more of their length. Usually partially overlapping.

PE: Peony type — Open-centered flowers with two or more rows of petals surrounding a disc. Petals may be irregularly formed.


WL: Waterlily — Closed center with multiple rows of ray florets normally broad and flat or slightly incurved, depth usually less than half the diameter.


ST: Stellar — Decorative-shaped flowers with petals being creased causing them to be narrow and involute with a slight recurve to the stem.

Size Codes

Size codes denote the approximate size of dahlia blooms that the tuber will produce. The sizes and their codes are: 

AA: — Flowers over 10" or more

A: — Flowers 8" to 10" across

B: — Flowers 6" to 8" across

BB: — Flowers 4" to 6" across

M: — Flowers up to 4" across

P: — Flowers up to 2" across