Hi, Elena, and welcome.
Rebloom on daylilies depends on fertilizer and water (just as with irises), though I personally think it is also a function of the plant's genetic heritage and your latitude. If you are trying to grow "southern" evergreen or SEv daylilies in NY, I can see the possibility of them not reblooming. You might instead want to try daylilies which have been bred to rebloom in more northern latitudes, so-called "northern rebloomers", such as SOME of those from the Ashwood Garden.
http://www.ashwooddaylilies.co... (Not all of his daylilies are northern rebloomers, so you will want to read what he has to say about each plant.)
