There are daylilies advertised as "re blooming." This seldom happens in Zone 5 or colder because our growing season is too short. This year has been an exception.
The early spring, wet summer and extended mild fall have been ideal for daylilies. As a result, they have bloomed at their peak performance, including re blooming.
There's a difference between the advertised descriptions (1) Continuous bloom (2) Re bloom (3) Late bloomer (4) Repeater/recurrent/extended.
Stella de-Oro, although listed as a re bloomer is more of a continuous bloomer. It does take a rest after the first heavy bloom before setting more flowers. They are typically the last flowering daylilies of the fall.
A true rebloomer has a normal bloom time and then simply sits without flowers until September when it may (note I said "may") set more flowers. Usually the ideal conditions don't happen. If the spring is late and/or early cold weather in the fall - the process doesn't happen.
A repeater/recurrent/extended is generally just a long sporadic bloom time and not so much a re bloomer.
A late bloomer is typically finished sometime in August. Of the four categories, I tend to pick this category because they seldom fail to bloom late in the season and they are at their peak performance.
I don't buy plants because I want or expect re blooming. The odds are against it here - this is my first year to have re blooming daylilies. And, even in an ideal year only a few of my re bloomers performed. Breeders and retailers will not guarantee re blooming in Zone 5. But, the price of a daylily is seldom increased simply because it has re blooming capabilities.