OV was an old favorite in Region 11 when I started my daylilies journey. It was registered in 1988 which means it is approaching its 30th anniversary which is old for a daylily. When I first planted it in zone 7 it clumped and bloomed like crazy. Lots of Oklahoma summer heat and every day it made me want some sherbet! Then I made a traditional gardening mistake. I figured it was doing so well surely I could get better performance by moving it. I dug an divided it and it never performed for me again.
Now I'm up at 8000 feet in zone 5/4 and I chose a perfect spot for it. (We love sherbet in New Mexico as well) and it sulked and pouted so I said to heck with that and stuck it behind some physostegia. Now it's flourishing and blooms galore.
I guess it's telling me not to try and tell it where to grow. By the way, it still shows on one of last year's pop polls.
Not bad for an old timer.