Sooby, there is no short and simple answer here.
I don't expect that I will ever be 100% rust free, as our winters simply do not get cold enough.
My purpose, as you put it, is to manage it, preferably without resorting to the use of fungicides. If one is willing to be ruthless and destroy new incoming plants that are rust buckets (provably so, in that they manifest rust in my garden), good control here can usually be achieved, due to a combination of climate (ours is not normally conducive to rust), culling (the rust buckets), and cutting and spraying with Dawn (an "organic" control) as necessary.
My first frank outbreak of rust was in 2006. Many plants were purged then. (It about killed me to destroy a large planting of 'Icy Lemon', one of my favorites at that time - but undoubtedly one of the most susceptible.) Since then, over the years I have bought new daylilies, some number of which shortly turned out to be rusty, most of which were destroyed. Those which were not destroyed were cut back and sprayed with Dawn, and I have not seen rust on them since. (If they had gotten rusty again, then they would have been purged. I have taken that approach since; badly rusty new plants are destroyed, some of those showing only light rust are given a cut-and-spray and a chance to behave. If they persist in rust, then out they go.)
So from 2006 to 2015 has been 8+ years of a relatively (rust-) clean and peaceful garden. The rust may have been lurking, but it was not visible (I did check for pustules), and that is good enough "control" for me. Right now the conditions are apparently right for rust, hence it is showing on a lot of plants (doubtless from new rusty plants bought in the interim) - hence the purge.
And while it is a hassle and a pain, it is also okay. I needed to downsize. The rust definitely made up my mind on some daylilies I was dithering over keeping or tossing
. My expectation is that things will settle down again later this year - and stay stable for some time, so long as I don't bring any more rust buckets into the garden. (I do have a problem with one of my few tet poly parents being rust susceptible; it has been given a cut-and-spray. I can't quite bring myself to purge that one (yet), but as it could potentially cause me grief down the road, I will have to keep a sharp eye on it.)
I expect that the daylilies in my garden would be boring to many people here. In part, it is a matter of my personal taste in daylilies, but it is also a matter of my culling most of the susceptible daylilies. With this latest outbreak, it has finally sunk in to me to not buy daylilies where there are rust prone ancestors in the background (with the exception of a wide consensus - not hybridizer hype! - that the plant is in fact resistant), no matter how gorgeous such daylilies look, and what AHS awards (!) they may have garnered. (Don't get me started on a rant...)
Getting back to your questions... The summary answer is: I don't expect to ever be rid of rust entirely, but I can usually manage it well enough. That leaves me with what to do with the pots of dirt (from which rusty daylilies have been removed). If there are viable spores in there, then I don't want to reuse it. If any rust spores in there will shortly die, then good - I can recycle the dirt into new pots.
