Being you are a newbie to daylilies, I also assume the plant is a newbie. It is not unusual for new plants in my garden to have rebloom scapes shorter than the first ones. Not always, and sometimes the scapes are taller than the first series, but that is normally after the plants have gotten established. I do suppose it could also be cultivar related, but I suspect it is just because the plant is new. Being in a pot also could be a contributor, but I don't actually grow plants in pots, I do keep some in pots just to give away, but I don't really grow them, they just mostly grow on their own. So I can't really say if growing the plants in pots would cause the rebloom scapes to be shorter.
