Larry - Yes, I thought about that too since my Raspberry Beret seemed to improve on it's rust resistance.
And you do have a point about the plants being healthy but became infected from their transplant into a garden bed that has some rust. The leaves are usually cut short when shipping. Those cut leaves are a point of entry for rust. So that would make sense that the immunity for many daylilies to fight rust is probably at it's all-time low during transplanting. So I absolutely agree that it would be wise to keep and grow any currently rust susceptible cultivars for a few growing seasons to see if their rust resistance improves. My guess is it might for some of them!
