The American Daffodil Society has a selection of daffodils that are designated as “ADS Miniature Daffodils.”
Currently, there is no definition for American Daffodil Society Miniatures. Below is a quote from the January 1964 issue of the American Horticultural Magazine. In the article titled “Miniature Daffodils” authored by George S. Lee, Jr., it provides some history of the challenge of defining Miniature Daffodils:
“Many years ago a group of members of the American Daffodil Society who were interested in smaller daffodils undertook to determine the species and garden varieties to which the term “miniature daffodils” might properly be applied. After repeated attempts it was realized that it was impossible to write a definition which would operate consistently to segregate from all the smaller daffodils a group which were truly miniatures. A daffodil flower is a living thing which changes from day to day and varies from year to year. The response of bulbs of the same variety is also subject to regional and cultural conditions. Therefore, it was concluded to compile an arbitrary list of species and garden varieties which, after careful field study, should be classed as miniature daffodils in the opinion of a number of competent observers. Surprisingly, the voting of personal opinions produced nearly general agreement.”
Today, the ADS Miniature Daffodil List has named cultivars only; there are no species on this list. This is because species daffodils are so variable: some may be miniature in size, and others grown in different conditions may be of standard size. Miniature-size species may be exhibited in ADS Daffodil Show classes for miniatures.
You can find a list of ADS Miniature Daffodils on DaffSeek.org by clicking on “Special Classes” in the upper left box titled “Other Queries.” Check the Miniatures box under American Daffodil Society and click on “Submit Query.” Click on a specific Miniature and read detailed information and view one or more photographs.
Here is the ADS Miniatures Daffodil list in a printable format: ADS Miniatures List, November 2016