Like Larry, I try to contain and minimise the rust I have. After trying to cook it by putting pots in full sun in our torrid summers, I nearly killed the plants and had plenty of rust. As Maurice has pointed out, the evidence is that strong heat stresses daylilies and does not kill rust.
After Sooby Sue kindly clarified to me that daylily rust is not systemic in the plant but is only in the green parts, I started to remove leaves as soon as there were signs of spores. I cut off half the long leaves to not shake the spores. Then I wipe hands on grass far away and return and pull the lower bits away. I try and do it before and after rain. Sue has said that a leaf must be wet for at least 4 hours for a spore to infect. They used to look great after rain for a week until spores broke out like crazy.
Where I have a strong plant that is covered in rust I remove all green parts (ragp) and cut the plant across fairly close to the crown. Often I replant these in a place where there is no rust. That has worked well so far even tho we have frequent showers, humidity or wind. Our low temps are very mild. Last night here was around 40 degrees, which is great for early Spring as we've already had nights with lows of 60 and humidity and peasoup fog.
I do not spray as I probably wouldn't get it all. If some plants become impossible I will bin them. I can't stand the look or feel of it. But when it last flowered my SPACECOAST RUFFLES even had spores on the scape, but I persevered and ragp without moving it, and it still look clean.
Unfortunately the first daylilies I ordered included some rated SS 5.0. They had no rust for a year until I got plants from 2 sellers claiming they had no rust. Some like DOUBLE PINK TREASURE, CLASSIC ROMANCE, HOT WIRE had spores when they arrived. Even APPLE TART developed spores so maybe it isn't AT. But better growing conditions often helps. Some that were terrible are now OK. Even MILDRED MITCHELL!!!
A big healthy leaf on a beautiful purple gladiolus developed similar looking orange spores. I cut it off at the corm, but it regrew well, complete with rust. I recalled a home remedy of milk for downy mildew on rockmelon/canteloupe leaves. So I throw diluted sour milk, cream or yoghurt over it and it sure kills the rust. Leaf looks bad too but better to my eyes. Hard to fget it oll over and would block a sprayer. Might pot the up so I can dip them. Glads in other parts of the garden are free of it, for now. Will try the sour milk product with frangipanis b4 they get big.
