One of Pat Cochenour's cultivars, LITTLE LEMON TWIST, is a prime example of a nocturnal, although she did not register it that way. I got it from her when it first came out. The next year, when it began blooming, it took me at least the first week (I live head each evening) of removing blooms to realize that-DUH!!- I was removing the old as well as most of the NEW blooms. The new blooms are fully open by at least 6 PM each evening. I still have to remind myself to be very careful to only remove old blooms. At 8 PM each evening, you must look carefully to see any difference. The old blooms re starting to look thin and wilted. Because the blooms are small, I still goof every so often!! I spoke to Pat about this before she died, but by then she was too ill to do anything about changing the registration data.