@Seedfork... Larry, I do not get rebloom on a lot of reblooming daylilies (but that is not true for all of them). To some extent that might be blamed on my casual approach to gardening (I am not fanatical about re-fertilizing during or after initial bloom), but that is not the entire story. As with poly blooms, I feel that rebloom (or not) is a function of genetics interacting with various environmental factors.
Some daylilies which consistently had a late summer to early fall rebloom at my old house, have not rebloomed here, despite additional fertilizer; I can only guess that the increased amount of shade they get here may (at least) be one factor, though I must truthfully also consider that irrigation amounts could also be a factor. ('Green Dolphin Street', which is the pollen parent of 'Osterized', is one of these, as is 'Bamboo Spitfire'.)
Some daylilies will occasionally throw out some rebloom scapes here, if they get extra fertilizer at/after initial bloom, but they are not dependable or consistent in this regard - though again, water restrictions could have played a role here. ('Newberry White Dove' and 'Pale Sun Rising' are two such daylilies; the former daylily gets full sun, so that should not be a factor in its rebloom behavior.)
Then there are those daylilies which consistently give some degree of late summer/early fall rebloom even if they *don't* get extra fertilizer (though additional fertilizer boosts the rebloom amount), and despite water restrictions and having to deal with a fair amount of shade. (These include 'One Fine Day' and 'Burmese Buddha'.)
If you were to talk to other daylily growers in the area, you may well get different answers. Most likely they are better about fertilizing than I am. Many of them may not have the same degree of shade in their gardens that I do. I am presuming that all of us are suffering equally under water restrictions, but that may not be the case - other people may have smaller gardens which allow them to focus their irrigation on the daylilies.
It is what it is, and I really have no complaints about sparse rebloom. Some daylilies, like 'Osterized', are worth the garden space, regardless. IMHO.
