Chrysanthemum Classifications

Today’s chrysanthemums are highly evolved flowering plants.  A member of the Asteraceae (Compositae) family, the Chrysanthemum is related to dahlias, sunflowers, marigolds, zinnias, and cosmos.  The genus Chrysanthemum once included more species, but was split several decades ago into several genera, putting the economically important florist chrysanthemum in the genus Dendranthema.  The placement of the florist chrysanthemum in this genus was very contentious.  A ruling of the International Code of Botanical Nomenclature in 1999 changed the defining species of the genus Chrysanthemum to C. indicum, giving the florist mum back its prized generic name.

The bloom which appears as a single flower is actually hundreds of flowers called florets. Two kinds of florets are present in a single bloom, disk florets and ray florets. For example, in the daisy-type chrysanthemum (class 7 below) each type of floret is easy to see – the outer parts are ray florets and the center or eye is composed of disk florets.  For ease of identification the National Chrysanthemum Society divides bloom forms into 13 classes.

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Class 1

 

Class 1 Irregular Incurve  These are the giant blooms of the chrysanthemum genus.  The florets (petals) loosely incurve and make fully closed centers. The lower florets present an irregular appearance and may give a skirted effect.  Bola de Oro (1992)  Flower Size: 6-8 inches.  Flower Characteristics: Grown as a disbud, plant moderately short.

 

Class 2

Class 2 Reflex  The florets in this class curve downward and overlap, similar to bird plumage. The tops of these blooms are full, but somewhat flattened.  Doreen Statham (1995)  Flower Size: 4-6 inches.  Flower Characteristics: Grown as a disbud, plant medium height. 

 

 

Class 3

 

Class 3 Regular Incurve  A true globular bloom equal in breadth and depth. The florets smoothly incurve and form a ball.  Heather James (1972)  Flower Size: 4-6 inches.  Flower Characteristics: Grown as a disbud, plant moderately short. 

 

Class 4Class 4 Decorative  A flattened bloom with short petals.  As in classes 1-3 the center disk should not be visible. The upper florets tend to incurve, but the lower petals generally reflex.  Chime (1994)  Flower Size: 5 inches or greater.  Flower Characteristics: Grown as a pot mum or disbud, plant height short. 

 

 

Class 5

Class 5 Intermediate Incurve  This bloom class is smaller than the irregular incurve, with shorter florets, only partially incurving with full centers, but giving a more open appearance.  Many of the popular commercial incurving types are in this intermediate class.  Bob Dear (1986)  Flower Size: 6 inches or greater.  Flower Characteristics: Grown as a disbud, plant medium height. 

 

 

Class 6Class 6 Pompon  A small globular bloom, somewhat flat when young but fully round when mature.  Size ranges from small button types to large disbudded blooms almost 4 inches in diameter.  The florets incurve or reflex in a regular manner and fully conceal the center.  Lakeside (1972)  Flower Size: 1-4 inches.  Flower Characteristics: Grown as a spray, plant height tall.

 

 

Class 7

Class 7 Single and Semi-Double  A daisy-like flower with a center disk and one or more rows of ray florets.  Crimson Glory (1978) Flower Size: Greater than 4 inches.  Flower Characteristics: Grown as a disbud or spray, plant medium height. 

 

 

Class 8

Class 8 Anemone  These blooms are similar to the semi-doubles, but have a raised cushion-like center.  Dorothy Mechen (1987)  Flower Size: Greater than 4 inches.  Flower Characteristics: Grown as a disbud, plant medium height.

 

 

Class 9
Class 9 Spoon  Essentially the same as the semi-double, except the ray florets are like spoons at the tips. The center disk is round and visible.  Kimie (1956)  Flower Size: 4 inches or greater.  Flower Characteristics: Grown as a disbud or spray, plant height tall.

 

 

Class 10Class 10 Quill  The florets in this Class are straight and tubular with open tips. The bloom is fully double with no open center.  Seatons Toffee (1996)  Flower Size: 6 inches or greater.  Flower Characteristics: Grown as a disbud, plant height medium.

 

 

Class 11Class 11 Spider  Spiders have long tubular ray florets which may coil or hook at the ends. The florets may be very fine to coarse.  Chesapeake (1997) Flower Size: Six inches or greater.  Flower Characteristics: Grown as a disbud, plant medium height.

 

 

Class 12Class 12 Brush or Thistle  Fine tubular florets which grow parallel to the stem and resemble an artist’s paint brushes or in the thistle form the florets are flattened, twisted and dropping.  Cindy (1987)  Flower Size: less than 2 inches.  Flower Characteristics: Grown as a spray, plant medium height.

 

Class 13Class 13 Unclassified or Exotic  Those blooms which fit in none of the other classes. They are often exotic, with twisted florets. They may also exhibit characteristics of more than one bloom class.  Lone Star (1986)  Flower Size: 6 inches or greater.  Flower Characteristics: Grown as a disbud, plant medium height.