The only registered one of mine that immediately comes to mind as fragrant is 'Osterized' - which is yet another yellow one.
I also have a seedling of lost heritage which is fragrant, but that one is a pink - lavender. I hope to acquire 'Hearts of Fire' this year, which is a red which is also supposedly fragrant. (I am not trying to get it for the fragrance - which I consider a lovely bonus - but because it has a rust digital score of 1.0.)
So it is not just the yellow daylilies that are fragrant, though maybe they are more likely to be fragrant than other colors...?
That is an interesting thought and a topic for database research, if one could trust the database to be complete, correct, and accurate in that regard (and if one had the time...). Of all the daylilies that are fragrant, what percentage of those are yellow? And does that percentage match the overall percentage of yellow daylilies among all daylilies, or are fragrant yellow daylilies represented out of proportion to their overall percentage in the daylily population?
(I have read (in more than one place), various people commenting that they would not have a yellow daylily in their garden, one reason being given was that they are "too common". While I would not go to the extreme opposite (only
yellow daylilies in the garden), I find yellow daylilies to be pleasant and cheerful (particularly so in the ML-L garden), and would not be without some, regardless of how small my garden was. Maybe the possibility that "yellow daylilies are (more) fragrant" might encourage some of the nay-sayers to incorporate a few of the fragrant ones in their garden?)