This is a very interesting subject for me. I have lots of seedlings outside in cups that are planted in the ground. But, they have been planted for varying periods of time (from several months to about a month) so I feel confident they will be fine. I think Stan has some more newly planted seedlings planted that are set on the protected side of his house (north Florida, not that far from me). I have few seeds in the refrigerator now that I noticed have sprouted and I was thinking of maybe planting them in cups and placing them outside also on the south side of the house, but I don't want to have to bother with bringing them in and out.
So after reading this thread, I have decided to go ahead and plant some of those seeds just to see how they do when planted at this time of year. I still have lots of seeds left in the fridge, so it will be worth the risk to me to know the answer. I also was surprised when I first learned that daylilies will sprout at much lower temperatures than I would have imagined. When new to daylilies I thought it would be the warmer the better, but I have since learned that very hot weather is a terrible time to try and sprout daylily seeds outdoors in Alabama. I had very poor success rates during the hot months here. Once the temps cooled down they seeds sprouted much better.