I've found that, too, but even when the info corresponds between websites, I think the reality is variable anyway. Even from year to year some of mine seem to bloom at different times! But in answer to your question "who do I believe?" I'd suggest going to the AHS database.

Here is a link that might be useful: AHS daylily database

Linnea,
The is often a discrepany between the registered bloom time and when a daylily blooms in a particular zone. I have three that were registered as lates - Dazzle, Ruffled Beauty and Uptown Girl. All three bloom EM for me. A daylily also can vary on its bloom time based on where in your yard it's planted. When I had Golden Prize planted in a sheltered area next to my barn, it always bloomed early. After I moved it to a colder, shadier spot it did bloom late. I had heard other people talk about Franz Hals being one of their latest bloomers. When it was planted next to my barn it was a midseason bloomer. When I moved it to a place with less sun exposure it bloomed ML, and was one of my latest bloomers this year. If I were you, I would look for late bloomers hybridized in a similar climate to yours. The daylilies of Reckamp and Klehm would be definite late bloomers for you.

Shive

I've been looking at northern growers for that reason: though there are sigificantly fewer of them to choose from.

So AHS is more reliable as a source of info than Tinkers? Too bad they don't have pictures! Though to double check bloom times for something I've already looked up I guess I don't need pictures.

I have 2 "new to my garden last year" cultivars that bloomed late for me. Khlem's New Tangerine Twist--a very pretty ruffled edged coral tangerine and Mariner's Cove by Pat Stamile--a ruffled pink. They both bloomed in mid to late August. Mariner's Cove had great bud count and branching and bloomed into September. I haven't looked to see how they are registered. I know a lot of them that are registered as early are sure not early for me. I'm in northeastern Illinois very close to Wisconsin in zone 5.
Beth

How late in the season are you looking for bloom?

Rose Emily (Pierce 1982) was blooming the end of August. It's a semi-evergreen listed as a "midseason" bloomer.

My last bloom ended the first week of August. I guess in my zone (5) that is the end of midseason. So what I'd like to get would be mid-to-late and late bloomers. I bought 11 new ones this year but was concentrating on color combos for my existing DLs. These were all from a southern grower so it's anyone's guess when they'll bloom next year. I'm a little concerned about buying evergreens. 7 of the new ones are evergreen or semi-evergreen: I hope they'll make it.

I'm also in northeastern Illinois: I should buy what Beth has!

That would be a start! Also share your concern re evergreens and semi-evergreens, though I've lost dormants, too. Have a couple new places to check out yet this fall - one nursery, two private parties. Maybe they can recommend some late bloomers...

All my DL's were out of wack this year. Some of my early bloomers didn't put up scapes until midseason and my late, late bloomer (Chicago Apache) finished blooming before Labor Day. In fact, here it is the middle of September and I have a bloom on 'Siloam Double Classic' and 'Beautiful Edgings' is on it's second bloom. I went out to my holding garden to plant my LA winnings yesterday and found a scape with three buds on 'Cousin Charles'. Maybe the crazy weather ahs something to do with it...I know here in So. Maine we had an extremely wet spring, followed by eight weeks of no rain.
Marilyn

I concur, Marilyn, with your view of DLs being out of wack this year. My Malaysian Monarch just finished blooming last week... Sept. 3-9... here in S. CT. That never happened before to me.
Molie

I agree that being a northern grower creates perplexing situations regarding bloom time.
Up until this year I never had much concern about Evergreen vs Dormant. Then this spring I experienced a loss on an evergreen, and some problems with frost damage leading to mush on some others that I was able to save -- all were evergreens. That said, however, this year I have tried a new tack. The evergreen that I lost this spring was planted WAY late in the season, and I'm sure had not established itself well enough, and otherwise might have survived. Also, I did not mulch, and there was little snow cover along with freezing/thawing cycles all winter long.
Many of my favorite daylilies are evergreens (many Munsons) and I continue to purchase evergreens, but more carefully in terms of planting times and mulching.
As for late bloomers, Orchid Corsage (dormant) is very late for me this year and still blooming now. It is a strong grower.
I found this list of hardy evergreens on the web somewhere (maybe posted here?) Here is the link.

Here is a link that might be useful: list of hardy evergreens

This is very useful, thanks! The evergreens I planted earlier were planted in spring; all look very good so should have healthy roots to survive the winter. Last few years we had no consistent snow cover. The bed is mulched but I can add more. When I make my final fall list (soon, I hope!) I think I'd better not have any evergreens to be planted this late.

Thanks too for the hardiness list; I've saved it.

Linnea,
You are wise not to plant evergreens this time of year. If I lived where you do, I don't think I would plant any type of daylily past mid-September.

Shive

I know Lime Frost is listed late but it started blooming for me the same time as everything else that was established in the garden, that being Rocket City, Spellbinder and Jolyene Nichole. Caused much confusion in my mind. I know I am also going to be looking for lates for the garden too.