Fungicide for Rust
enoughcliches
17 years ago
Featured Answer
Sort by:Oldest
Comments (10)
Kimmsr
17 years agoenoughcliches
17 years agoRelated Discussions
when to expect my hollyhocks
Comments (8)After the late season freeze (Feb) and record breaking March rainfall the PNW experienced. I am not surprised that many plants have taken a big hit. In my role as a garden consultant, I have seen all manner of even very hardy plants bite the dust this season. The combination of a pretty mild winter and the early end of dormancy for a lot of plants followed by a 1-2 weird weather punch was just more than they could handle. Couple that with hollyhocks' typical short lifespan and I'd think it was time to replant with fresh plants :-))...See MoreRust bucket daylilies
Comments (44)I probably shouldn't speak for your climate, because maybe it isn't quite the same as mine, but my point was that at least in my climate there is a time of year (summer) when the temperature is in the 90s or higher during the hottest part of the day and it barely gets below the 80s most nights. During that time, rust is mostly dormant. If your plants had a lot of rust in the spring, they will look bad in the summer because the leaves will die back uglier in the heat than they would if they didn't have rust. Then there is a time of year (spring/fall) when the temperatures range through the 60s and 70s most of the time, even though the high temperature might be higher. This is when rust loves to grow and spread. And there is a time of year (winter) when the temperatures are below 60 overnight and sometimes during the day. Again, rust will slow down, and your more dormant daylily foliage will die back. But you're right -- around here the winter is a mix of this and more moderate days. If you prevent rust during the spring and fall weather, new rust will not appear during the summer and winter weather. If you have rust during the spring and fall weather, it should mostly slow down during the summer and winter weather, although it may spread when the temperatures are unseasonably moderate. I'm going back over my notes, and this year I allowed rust to spread unchecked until mid-March in order to evaluate plants for hybridizing. Then I used Cabrio + chlorothalonil on the "public" plants in the front yard March 19, March 26, and April 11. I might have sprayed once in May and forgotten to record it. Over the summer, all the new foliage looked good and the old rusty foliage died back. Then this morning I sprayed again for the first time since spring because we had a cold front that brought daytime temperatures into the 70s with highs maybe hitting the 80s the last couple days. I have rust in my garden, and I control it as well as I feel I need to so that the front yard looks ok to me. To do this doesn't take a lot of work. And I allow it to spread naturally in my seedlings so that I can evaluate them for rust resistance. Nate...See Morerust
Comments (56)Nancy, I don't have rust yet, but I've been very interested it's control and management from the (recent) start of my hobby. One thing I thought could be more emphasized regarding the common systemics in rotation now is that they are not 'true' systemics. They do not move DOWN from their point of absorbtion-only up. A true systemic moves up and down, but they seem a bit rare. It will be important to spray very low, you see. It won't be enough to spray from above and let it drift down, but far better to spray the base of the fans, from all sides, and into the midst of the base. To my mind, this fact alone explains why rust is not eliminated in most gardens. The AHS recommends cutting the infected plants, and nearby apparently healthy plants, to the ground so perhaps this point is not so important. Or perhaps they should be dug out to expose the crown before spraying. A recent link was posted about Kphite systemic fungicide in regards to controlling crown rot, and the first thing I noticed was the mention of Aliette (a true systemic, but made with aluminum---eek!)--and that Kphite was also a true systemic fungicide, moving up and down through the plant but made with potassium. I have no idea whether Kphite would be at all effective against rust, but it seems worth investigation, especially as it's apparently used by southern hybridizers as a rot remedy. Kphite and Aliette also stimulate the natural immunity of the plants. I suspect you may have already removed the leaves from your obviously infected plant. If not, be sure to wet them with some sort of contact fungicide to avoid spreading the spores as you bag them. Cut that plant to the ground. I also found a study pointing out that withing three days of inoculation, treating other plants with a contact fungicide merely wiped out the healthy, defensive population of beneficial fungi making rust more difficult to control. Theoretically, the internal rust lives in the leaves alone, and a Japanese article claims that when the plants are cut to nubbins the regrowth will be rust-free. (I nubbined and bleached some of my new arrivals this summer and nothing died from it.) The thing is, rust is so widespread that reinfection seems likely. It's also possible that the first plant you notice with rust is simply the least able to defend against infection. There may be another plant with such a mild case, only a few pustules, that you've not noticed. The AHS rust page also still recommends cutting nearby plants to the ground, even if apparently healthy. You find the rust page in the daylily dictionary, and it's consistant with most everything I've read. Bear in mind, these are the ramblings of someone with zero actual experience-- I only wanted to be prepared, and I found it all quite interesting. The only plant I thought had rust, turned out not to have it. I had strange plans about potting it up and putting it into my freezer. LOL! That little wacko idea never got tested...so far. Anyway, I'm feeling pain for you, and wish you good luck....See MoreAzalea rust?
Comments (3)There are thousands of species of rust that attack different kinds of plants, and not all fungicides that fight rust can be used on all plants. Some of the different fungicides cannot be used on the same plants within a certain time frame or the combination of the two can burn the foliage and can even kill the plant, and some of the things you'd use for rust can damage plants if used in hot weather, so......just be sure you read the fungicide label and make sure the one you buy can be used on azaleas in high temperatures. Most product labels can be found on the internet by Googling so that you can read them before you even go to the store to buy a fungicide. The products most commonly used for various kinds of rust are organic products like sulfur (available as both a dust and a liquid), neem oil, and copper and then there's the whole group of synthetic herbicides like chlorothalonil (found in products like Daconil and Ortho Max Garden DIsease Control) and mancozeb. I imagine that chlorothalonil is labeled for use on azaleas, but I haven't grown azaleas since the 1980s so I don't know that for sure. You also can use bordeaux mix for azalea rust, but I don't know if you can use it when the weather is as hot as it is now Whenever you have rust on anything, the standard method of treating it is to remove the rust-infected leaves so they do not continue to reinfect new foliage and to spray with a fungicide labeled for rust control on that specific type of plant. Also, rake up any rust-infected leaves that have fallen to the ground. Understand that once you have rust, it is hard to cure it in the current season. The use of fungicide sprays on a regular basis (most product labels will specify the interval of days in between spraying, and it can vary from 7 to 10 or more depending on the product) can keep the rust under from spreading and getting worse. Most fungicides work in one of two ways: either they coat the leaves (so be sure to spray the undersides of all leaves too) so new fungal spores cannot attach to them, or they change the pH of the leaf surface and make it a pH that is not in the right range for the rust to grow. If I had rust on azaleas this year, I'd spray this year to keep it under control this summer and autumn, and then I'd spray preventively with a fungicide in spring to try to keep it from reappearing and establishing itself next year. With most garden plants, spraying preventively is more effective than beginning a spray program after fungal diseases already have shown up, So far this year, I've only had rust on hollyhocks and beans, With both, I just kept removing the diseased leaves so it wouldn't spread to new foliage. The beans put out lots of new foliage and the rust stopped being a problem after we went a week or more without rain. The hollyhocks never really cleared up, and I didn't spray them with anything because it was raining daily for so long. I've cleaned up the rusty hollyhock foliage now, and we've been dry for a while, so I'm hoping the cycle of rust infection on the hollyhocks has ended for this year. Now, since there's so many different kinds/brands of products that contain sulfur, copper, neem, chlorothalonil and mancozeb, it would be hard to guess which products will be on the store shelves in any given area at any given time. I often find it easier to find a fungicide at this time of the year in a full-line nursery or at an ag farm supply store like Tractor Supply or Atway's. At big box stores like Wal-Mart, you often can still find neem oil or Daconil in July if your store hasn't already started shoving gardening products out the door to make room for school supplies. Because there's so many different kinds of products available, (the TSC near me carries the Southern Ag brand), I found a document from Clemson that has a whole page that lists many of the available products for azalea rust....it lists them by brand names under each category. I've linked that document below. Hope this helps, Dawn Clemson Univ Document on Azaleas...See Moredchall_san_antonio
17 years agoenoughcliches
17 years agontbio
17 years agoenoughcliches
17 years agontbio
17 years agoenart
17 years agoandistamayo
14 years ago
Related Stories
GREAT HOME PROJECTSWhat to Know About Adding a Reclaimed-Wood Wall
Here’s advice on where to put it, how to find and select wood, what it might cost and how to get it done
Full StoryGARDENING GUIDESGreat Design Plant: Cannas
Easy to grow and maintain, these showy, colorful plants are perfect for beginning gardeners
Full StoryTREESGreat Design Plant: Downy Serviceberry
Plant this sculptural tree in fall or spring for year-round interest and graceful beauty
Full StoryGARDENING GUIDES6 Wonderfully Easy Roses for Any Gardener
Look like an expert even if you're just starting out, with these low-maintenance gems of the rose world
Full Story
Kimmsr