ADS (registered) dahlias are assigned a 4-digit classification number, depending on their size, form and
color. The formula used for assigning the numbers may seem a little complicated at first, but once you
have a good overview of how it is done, it becomes a great tool for helping growers to identify their
cultivars. The classification number is used when exhibiting in shows. It is also used in documentation,
and by sellers.
At a high level, color is part of the 4 digit classification number. There may also be more detailed color information assigned.
The following documents provide more detail.
Understanding Classification Numbers
ADS Dahlia Classification and Number Guide