I don't think daylilies in general care what year of growth they are in. In the growing conditions hybridizers use in Florida they get bloom in nine months. Researchers at Michigan State University found that daylilies do not require a cold period to flower nor do they require specific day lengths (they could only test a small sample of the thousands of daylily cultivars so it is possible that there are some cultivars that are different).
I think that in general each daylily cultivar or seedling will bloom when it reaches a minimum size (depending on the environmental conditions it experiences). Plant size will depend on how well it is grown and for how long. Arisumi found that optimum temperatures for daylilies are between 75F - 85F. I expect that they are probably closer to the 75 degree end of that range. They need plenty of light for optimum growth and should be fertilized. Competition from weeds should be eliminated and clumps should not be allowed to get large as the fans probably compete with each other. As a rule of thumb Munson advised that daylilies should be divided each year (but his experience was with their growth rates in Florida and he probably had a one to eight increase ratio [or better] per year). He indicated to some of the hybridizers he mentored that daylilies would suffer if not divided frequently enough.
