Ginny,
Check the parentage of new intros you/your grandson really like, and use the ones in your collection that have proven to produce good seedlings already.
Karol Emmerich's catalog has information about which ones of hers are good parents and what type of offspring they are producing (with photos of seedling blooms).
For future reference, during the dormant season, she is quite willing to share advice on daylily hybridizing over the phone. She is a delightful lady.
