The information below has been taken primarily from the 1989 International Daffodil Checklist published by the Royal Horticultural Society, London, however, there have been some modifications.

• The classification of a daffodil (Narcissus) cultivar will be that submitted by the person registering the cultivar, or will be based on the description and measurements submitted by such person.
• The classification will consist of a division number and a color code for the perianth and corona (for example, 1 Y-Y, 2YW-Y, 3W-WWR, or 4Y-O).
  
• The numbered divisions in which a daffodil cultivar may be placed are defined and illustrated under Description of Divisions.
• Measurements taken in determining classifications between Divisions 1, 2 and 3 will be those of the flower at maturity (Full Flower). The length of the perianth segments is the measurement from the tip of one segment when flattened out to the base of the corona. The length of the corona is the measurement from the base of the perianth segments to the furthest margin of the corona.
• The colors and equivalent code letters which may be used to describe a daffodil (Narcissus) cultivar are:

  White or Whitish	W
  Green	G
  Yellow	Y
  Pink	P
  Orange	O
  Red	R

  In distinguishing Orange from Red in daffodil classification, borderline colors, including and on the yellow side of Royal Horticultural Society Orange Group 29, are said to be Orange. Those, including and on the purple side of Orange Red Group 30, are Red.

  • The color code will consist of two letters or two groups of letters separated by a hyphen: the letter(s) before the hyphen will describe the perianth segments (the "Petals"); the letter(s) following the hyphen will describe the corona (the "Trumpet" or "Cup").
  • For purposes of description, the perianth segments will be divided into three zones: outer zone, mid-zone and base; and the corona into three zones: eye zone, mid-zone and rim.
  • If the perianth segments are substantially of a single color, a single code letter will describe them. If they are of more than one color, either two or three code letters will be used, describing the outer zone before the mid-zone and/or base.
  • If the corona is substantially of a single color, a single code letter will describe it. If it is of more than one color, three code letters will be used, describing the eye-zone before the mid-zone and rim.
  • In double daffodils (Narcissus), the code letter(s) before the hyphen will describe not only the perianth segments but also any extra perianth segments (being of the same color), even if they are interspersed with the corona at the center of the flower. The code letter(s) following the hyphen will describe the corona or the segments of the corona. Multiple letters before or after the hyphen will, in doubles as in all other daffodils, indicate that there is more than one color from outer zone to base of the perianth segments or from eye zone to rim of the corona or the segments of the corona.

Description of Divisions

DIVISION 1 - TRUMPET DAFFODILS OF GARDEN ORIGIN		DIVISION 2 - LARGE-CUPPED DAFFODILS OF GARDEN ORIGIN
One flower to a stem; corona ("Trumpet") as long as or longer than the perianth segments ("Petals"). Photograph: `Dutch Master'		One flower to a stem; corona ("Cup") more than one-third, but less than equal to the length of the perianth segments ("Petals").   Photograph: `Ice Follies'
DIVISION 3 - SMALL-CUPPED DAFFODILS OF GARDEN ORIGIN		DIVISION 4 - DOUBLE DAFFODILS OF GARDEN ORIGIN
One flower to a stem: corona ("Cup") not more than one-third the length of the perianth segments ("Petals").   Photograph: `Barrett Browning'		One or more flowers to a stem, with doubling of the perianth segments or the corona or both.   Photograph: `Dick Wilden'
DIVISION 5 - TRIANDRUS DAFFODILS OF GARDEN ORIGIN		DIVISION 6 - CYCLAMINEUS DAFFODILS OF GARDEN ORIGIN
Characteristics of N. triandrus clearly evident: usually two or more pendent flowers to a stem; perianth segments reflexed.   Photograph: `Thalia'		Characteristics of N. cyclamineus clearly evident: usually one flower to a stem; perianth segments reflexed; flower at an acute angle to the stem, with a very short pedicel ("Neck"). Photograph: `Jack Snipe'
DIVISION 7 - JONQUILLA DAFFODILS OF GARDEN ORIGIN		DIVISION 8 - TAZETTA DAFFODILS OF GARDEN ORIGIN
Characteristics of the N. jonquilla group clearly evident; usually one to three flowers to a rounded stem; leaves narrow, dark green; perianth segments spreading not reflexed; flowers fragrant.   Photograph: `Trevithian'		Characteristics of the N. tazetta group clearly evident; usually three to twenty flowers to a stout stem; leaves broad; perianth segments spreading not reflexed; flowers fragrant.   Photograph: `Minnow'
DIVISION 9 - POETICUS DAFFODILS OF GARDEN ORIGIN		DIVISION 10 - SPECIES, WILD VARIANTS AND WILD HYBRIDS
Characteristics of the N. poeticus group without admixture of any other; usually one flower to a stem; perianth segments pure white; corona usually disc-shaped, with a green or yellow center and a red rim; flowers fragrant.   Photograph: `Actaea'		All species and wild or reputedly wild variants and hybrids, including those with double flowers.   Photograph: N. canaliculatus
DIVISION 11 - SPLIT-CORONA DAFFODILS OF GARDEN ORIGIN		DIVISION 12 - MISCELLANEOUS DAFFODILS
Corona split rather than lobed and usually for more than half its length.   Photograph: `Orangery'		All daffodils not falling into any one of the foregoing Divisions.	Division 12 is not illustrated due to the wide variation in shape and size between the flowers involved.
NOTES: The characteristics for Divisions 5 to 9 are given for guidance only; every characteristic is not necessarily expected to be present in every cultivar assigned thereto.

Consumer Horticulture | Bulletin 41: Narcissus