Hmm... most of mine that (thus far) have been unaffected *are* listed in the ATP database as having some degree of resistance.
A few unrated plants that (thus far) have not shown any rust include:
'Osterized'
'Sears Tower'
'Winning Note'
'Hip to be Square'
'Pale Sun Rising' (this one, for a certainty, was in the garden long enough to have survived the great rust purge in 2006)
I've had all of these for many years, and so far, so good (although that could change). H2BS is planted right next to 'Polly Wolly Doodle' which got quite a bit of rust this year, but so far is holding up. 'Osterized' (planted one rose away from 'Polly Wolly Doodle') surprisingly has been rust free thus far; "surprisingly" since one of its parents, 'Green Dolphin Street', got quite a bit of rust back in 2006. We're in the midst of a few days of rain right now, so it may be that I'll have to come back and say "oops"...
Plants that are newer, planted somewhat near to plants that got rust this year, but have not yet shown signs of rust include:
'Sun Silk'
'Small World Edwin Keith Smith'
No guarantees on any of this, of course, and your climate is quite a bit more humid than ours, which I think would translate into more problems with rust. Daylilies that aren't problematic for rust here, might well be for you.
And there are always surprises. 'Wonder of it All', which I had read (on other forums) was resistant, got a visible degree of rust this year, enough so that I am considering purging it. 'White Wolf' and 'Victorian Lace', the first of which has had rust as a new plant, the second of which has a reputation for rust, thus far (this year) are clean.
One thing that I have been working on this winter is doing ancestry research on my daylilies, with regards to susceptibility or
resistance. The ATP database has been wonderful for that.
It is quite interesting what turns up...
For example, every plant that I have ever owned that had 'Wild Cherry Round Up' somewhere in its ancestry (not just as a parent, but going further back), ended up getting rust - although to varying degrees. WCRU is not rated in the database (and I have never grown it myself, so I cannot say), but both of its parents are rated as being susceptible, so it would not surprise me in the least that it, also, is susceptible. Does this mean that every and all daylilies with WCRU in their background will be rust susceptible? Not necessarily, particularly if WCRU is farther back in the ancestry and/or the other parents all have resistance, but it is enough of a red flag that I would not now buy a daylily with WCRU in its ancestry, unless it was a high percentage polymerous tet (since such plants are still uncommon) or there was wide consensus that the plant was resistant.
Other plants that got rust this year, when their ancestry was researched, similarly ended up showing rust-prone parentage.
On the other hand, some (newer, for me) plants that are still rust free, have parents which are listed as being resistant. 'Small World Margarita' is one such plant; both of its parents are resistant.
Going forward, both for purchasing garden plants and also for my pollen dabbing, I am going to research any and every plant before buying it or using it. For a lot of daylilies there is no rust susceptibility information available, however... and not just for them, but also for their parents (no parents are listed, or the parentage is given as "Sdlg x Sdlg"). In such cases, I assign such plants a neutral or borderline rating (which I think is roughly a 2.5 on the ATP scale of 1.0 - 5.0), and proceed with caution (because the 2.5 rating could be a best case scenario).
So if you are considering a particular plant, hit the database and scrutinize its ancestry. If you are just looking for a resistant plant of a particular color, search the database for resistance in daylilies of that color. Another approach would be to start with a known resistant plant (in a color that you want) and forward search its children plants. While the children plants may not have rust ratings, you can sometimes make a good guess how they will behave given the resistance (or not) of the other parent(s).
I hope that is helpful to you - and I am glad to see that I am not the only one wanting to populate their garden with resistant daylilies.
