Hi Lisa, not sure if you've had any luck finding the daylily Lisa (1965), but going on the clue that Char gave, here is a link to a Chicago newspaper article from 1970 entitled Annual Daylily Show to open in Hinsdale.
https://www.newspapers.com/new...
Here is an excerpt:
The show, sponsored by the Chicagoland Daylily Society, will be open from 2 p. m. to 5:30 p. m. There is no admission charge. "Anyone interested in day-lilies is welcome to enjoy seeing the fine array of blooms that will be displayed," said Mrs. Marie Fischer of Hinsdale, society president. "T h e abundant spring rains and recent warm weather have produced exceptional specimens which should make this year's show one of the best on record."
The Chicagoland Daylily Society started in 1963 and is still around. Maybe contacting one of the club officers would help.
http://www.chicagolanddaylilys...
Edited to add: There is also a page with CDS hybridizers. You can contact them by clicking on their name.
