It seems we are in the same zone. What part of FL are you in ? I usually just trim out the rusty foliage after they finish blooming. You can spray with fungicides that list rust on the label if you want but any rust I might have left after removing the foliage that's damaged disappears once it starts to get really hot. You can spray again in early spring to nip rust in the bud.
Linda

Hi. I am in Palm Bay on the east coast, just above vero where they say, "the Tropics begin." Is it too late to spray for rust. In my back yard the foliage really looks horrid and one of the beds in my front yard. Taken by Storm has very large leaves and htey look so ugly. Also in the back they are near food plants so I would have to spray with something that is not poison. I hate looking at those leaves. Would it be bad to cut the foliage now?

I'm in the Orlando area and I just live with the ugly foliage until after they bloom and then I give them a hair cut.

Is it bad to trim the leaves? I really need to treat them. The leaves that have it seem to die and it also spreads. ??

Sorry you have rusty plants.
It's going to be really hard on the plants to cut the foliage back and let them bloom too.
I also would not want the daylilies intermingled with veggies if I wanted to try to treat the rust. You need to spray the daylilies more often than recommended for the veggies.
All the best fungicides are very expensive and hard to come by in small quantities. I would try to contact a local daylily club. Maybe they have a source and some advice for spraying the fungicides, or maybe where you purchased the daylilies. If they are rusty for you, they probably were for who sold them to you.
I would recommend any one of the following fungicides to treat and prevent rust on daylilies: Headline/Cabrio EG, Compass and Stratego. Be sure to use spreader stickers with them.
Good luck, Ed

Thanks, Ed. There is no daylily club really nearby. For my front yard daylilies, I have Fertilome Systemic Fungicide. Is that good? I can't use that in the back yard where my veggies and herbs are. Some of these plants I've had for years and they've never had rust til this year. It just came to the back yard this year. My "Taken by Storm" in the front, but another bed, has it for the first time. Taken by storm has huge leaves so the rust really makes it look horrid. I'll contact my daylily vendor as well. He's in another part of the state, but very nice. The local nursery told me they found neem oil helps with rust, but you have to spray often.They were out of it, and I thought I'd ask here first before purchasing. I have not seen any of the fungicides you mention. Yikes! What are spreader stickers. ????? Thank you, Ed.

The Fertilome is not effective for daylily rust.
You can use Neem Oil, but be very careful not to use it too strong, or it will kill your foliage, especially when hot. I probably would not recommend using at this time of year.
You can use Ultra-fine Oil and Dawn dish-washing liquid at 5% solution. Commercial fungicides; Daconil and Mancozeb. All the above only kill what they contact, so the rust does continue to live inside the leaves, but they will provide some relief for the plant, and maybe will get you past the stage where the rust is active. Usually when it gets hot, the rust will become dormant and not appear again until fall.
You will need to spray weekly to bi-weekly. Some plants, like the TAKEN BY STORM may need to be sprayed more often.
It sounds like a new plant brought rust into your garden. You or your pets have unknowingly spread it to your other beds. The first outbreak you have will usually be the worst. Many plants seem to acquire some immunity to the rust.
Spreader-Stickers are compounds that help keep powsers in suspension when mixed with water. They break surface tension which allows the fungicides to penetrate the foliage surface. They make the fungicide application more effective. Typically, use them with powder/water mixtures. Adjusting the pH of the water can also help. You want neutral to slightly acidic solution.
Hope this helps, Ed

You can find spreader-stickers for reasonable prices on Amazon. I bought a Bonide Turbo spreader-sticker and it has worked fine.

The first outbreak you have will usually be the worst. Many plants seem to acquire some immunity to the rust.

Interesting! I thought I was just getting used to the rust so it didn't seem as bad.

Nate

I live in Florida so have had rust before, but this year it has spread to other daylily plants and daylilies in other beds. Ed, how hot will stop the rust.? We're in florida. It's already in the 80s during the day. Here I've been spraying with this stupid ferlilome and it doesn't help daylily rust??!! :( I don't have any new daylilies this year. You have me lost here Ed:
Typically, use them with powder/water mixtures." What powder? "Adjusting the pH of the water can also help> How do I adjust the PH of the water? And what water? do you mean the water I water with??? Yikes. I am in over my head here.

Thanks Nate and Ed. I just googled Spreader Sticker. It sounds sort of like a machine like fertilizer spreader and the word sticker had me really confused. but I see it's just liquid.The prices of some are really high. How do I know how much I need? thanks so very much. Are you saying to mix the spreader sticker with something like Daconil??

Here's roughly what I use:

Since I'm only spraying about 20 or 25 daylilies in the front garden, about 1 quart of mixture works well for me. I have a pump type sprayer that holds a little over a quart.

I don't remember off-hand the exact amounts, but it's something like:
1/4 tsp Cabrio
1/2 tsp chlorothalonil fungicide (like Daconil)
1 tsp spreader-sticker
Then add water to fill and swirl to mix.

So you really don't need much unless you have a huge daylily collection. That's why it's frustrating that Cabrio comes in a gigantic package that costs over $100. Everything else can be bought fairly cheaply in a home & garden store or online. I've had the same little baggie of Cabrio from my local DL club for two years now, and it's probably going to last me two more at the rate I'm using it.

Nate

Sorry. The classic scenario is buying a new daylily and bringing it home only to infect the existing daylilies with rust. Apparently you have had rust and it has been slowly progressing throughout your garden. Sometimes conditions are prime for rust growth and this may explain the worse than usual outbreak you have this year.

Rust should die back when daytime temps consistently get into the 90's. This occurred in June for me in Houston, which has a similar zone to yours.

Unfortunately, most systemic fungicides available on the market, especially the cheap ones, are not effective against daylily rust. Nate is fortunate to have a daylily club that buys the expensive fungicides and then distributes them in small amounts to its members. Living in Florida, you can probably buy a small amount of effective fungicide from one of the many daylily hybridizers/growers in your area.

As Nate says, he uses a small pump up sprayer and mixes:
Cabrio: a systemic fungicide that has proven very effective killing rust spores (those orange spots on the outside of the leaves) and the rust inside the leaves. This comes as a fine powder and should be used with a spreader/sticker for best results.
Daconil: a contact fungicide (chlorothalonil) that kills the spores on the leaves, but not the rust inside the leave. But very effective killing the spores to keep the rust from spreading. I don't think using a spreader/sticker is as important with this fungicide, but read the directions.
Spreader/Sticker: usually a liquid that reduces surface tension to give better coverage and wetting of the leaf and allow the fungicide to stay on the leaf longer and penetrate the leaf. These are usually very concentrated and most are fairly cheap. If you don't get the spreader/sticker, at least use about 2% Dawn dish-washing liquid with your mixture.
If you're not sure of the pH of your water supply, use about a teaspoon of vinegar per gallon of water. Close your sprayer and mix well. Mix each time you have to pump the sprayer up again.
Most hybridizers/growers have their own preferred mixture to treat rust. So be open to some difference, but I would be skeptical if they don't include one of the above recommended systemic fungicides.
Ed