sooby said:For pest control I use a commercial insecticidal soap, like Safers, that is made specifically for plants. It is organic (OMRI listed) whereas "big brand" kitchen dish soap would not technically be considered organic if that's important to anyone (and is not really soap but detergent).

Sue,

There's a concoction that I keep around in a hand pump sprayer for use against various insects. It started with Neem Oil, and since the mixing directions called for a surfactant, I used Safer's Insecticidal Soap—mixing both products per label directions, resulting in what is theoretically an organic, insecticidal, "double-whammy". In a narrow stream, it's amazing for knocking Yellow Jackets and Narcissus Bulb flies to the ground in mid-flight, and is very effective for spider mites and aphids as well.

I'm starting a small-scale soap experiment. There are three pots of evergreen daylilies that I have been bringing inside the house every night this winter. One pot has 3 large seedlings; To The Limit x (J.T. Davis x Ed Brown), another has 4 small seedlings; The Blessings of Freedom x Red Blooded, and the third contains three small fans of The Blessings of Freedom. After a long period of drizzly and rainy weather, I started to see a few pustules on them. I'm not seeing much if any new rust in the garden due to the cool weather, but the 60°-64° nights inside, coupled with the wet conditions outside, are letting rust develop on these "inside" plants. The warm, dry nights also resulted in an amazing outbreak of spider mites. I'm now in my second week of applying the Neem/Safer's solution to them, and hopefully I'll be able to determine if the spray is effective for controlling rust. Interestingly, the "inside" plants aren't showing significant growth advances over many other evergreen seedlings that are spending the winter outside. (They're simply warmer at night, they're not being given supplemental light.) Of course, it's not much of a winter yet - frosts have been light and infrequent.

There must be a high level of translocation going on with the systemic fungicides, as it would seem to be practically impossible to thoroughly wet the lower leaf surfaces of daylilies.

In his 2016 catalog descriptions, Jamie Gossard reports some significant plant growth and performance enhancements resulting from the use of fungicides in the strobilurin family, due to an increase in photosynthesis. (Cabrio, Headline...)

http://heavenlygardens.com/ima...

This was the first I've heard about this growth-enhancing effect. I've found a few research papers which compared wheat production between treated and untreated fields, but the increases in production seemed to be simply the result of healthier plants. I wonder how many people will be tempted to use these fungicides as photosynthesis enhancers. In order to verify those effects, a controlled study would need to be done using rust-free plants, or plants treated with another family of fungicides as a control group.

A couple of other thoughts regarding the soaps. If they prove to be effective, it would be nice to know by what means they work. I would guess that by thoroughly wetting the spores, their ability to be blown around is diminished, which might go a long way toward reducing the spread of rust. Or, it might be that by wetting the spores, they are encouraged to "sprout" right there at the original infection site, much like pollen can be prematurely sprouted with moisture and rendered ineffective.

CaliFlowers said:
This was the first I've heard about this growth-enhancing effect. I've found a few research papers which compared wheat production between treated and untreated fields, but the increases in production seemed to be simply the result of healthier plants. I wonder how many people will be tempted to use these fungicides as photosynthesis enhancers. In order to verify those effects, a controlled study would need to be done using rust-free plants, or plants treated with another family of fungicides as a control group.

Yes, you'd have to separate the effect of simply controlling the rust since rust itself decreases photosynthesis. Given the cost of the strobilurins I would have thought a bit more attention to fertilizer and other cultural practices would be more cost effective for improving plant performance minus rust, not to mention that there are label restrictions on the usage and the number of total and consecutive times one can use strobilurin fungicides because of their high risk of causing fungicide resistance.

CaliFlowers said:
A couple of other thoughts regarding the soaps. If they prove to be effective, it would be nice to know by what means they work. I would guess that by thoroughly wetting the spores, their ability to be blown around is diminished, which might go a long way toward reducing the spread of rust. Or, it might be that by wetting the spores, they are encouraged to "sprout" right there at the original infection site, much like pollen can be prematurely sprouted with moisture and rendered ineffective.

Dishwashing liquid was tested in a university research study for daylily rust and was relatively effective, which is where the idea came from initially. They didn't look into how it worked as far as I recall but there are commercially available fungicidal soaps so the mode of action may be mentioned somewhere.

Living in the south, rust is as common as air, and I just dont get to worked up about it. I do spray with soap, and will spray a fungicide. Im more worried by the thing that effect the buds and the flowers. Ive never heard of rust killing a plant.

I use the soap alone to sufficate....I use with fungicide to help the chemical stick to leaves.

Jamies info interesting

This paper has some interesting information: Fungicide impacts on photosynthesis in crop plants.
It is available http://www.researchgate.net/pr...

Maurice, I found this one which implies that where there was an enhanced effect it is not necessarily due to increased photosynthesis (e.g. one had increased nitrate assimilation). One cited article where they found an increase turned out to be because the strobilurin delayed leaf senescence of an annual crop, similar to what is mentioned in your article. The conclusion at the end of this specific article linked below was that the strobilurin did not increase yield over and above the effect of controlling disease. In another that I saw there was actually a reduction in net photosynthesis

http://extension.agron.iastate...

Of course, none of these references is specifically about daylilies and daylily rust.

I meant to post this about rust. Im pretty sure someone in the past has posted, but here it is again.

http://www.lilyfarm.com/rust.h...

This report is interesting in that it also looks at unpublished trials (but on corn)
Are Fungicides No Longer Just For Fungi?
An Analysis of Foliar Fungicide Use in Corn
at http://www.apsnet.org/publicat...
The research I noticed where the strobilurin delayed the leaf senescence (of the flag leaf?) promoted the increase in photosynthesis due to that delay. That might lead one to simply look at the final effect or changes close to it.

For some reason I thought daylily rust would be a major problem there in Japan, especially since they seem to have the host plant for rust growing there. I realize this info is from a web site, anyone know if it is for sure true? Why would they not have rust on cultivars just like here. I assume being it does show up on species that it is not the climate that is preventing it on cultivars?


"In Japan, daylily rust is commonly observed on wild Hemerocallis species but rust outbreaks have not been reported for daylily cultivars on residential properties or public botanical gardens. It is unclear why the disease has not been problematic in Japan."
http://www.apsnet.org/edcenter...

Larry, your link, like Maurice's, is from the American Phytopathological Society and written by two specialists in daylily rust, so therefore should be credible concerning plant diseases. In fact one of the authors, Dr. Ono, years ago supplied me with the images of infected patrinia and the life cycle images of daylily rust for my daylily rust info site. I co-authored two articles with him for the AHS's Daylily Journal on daylily rust and hosta rust. He did tell me the same thing but apparently they don't much grow daylily cultivars in gardens in Japan anyway. I don't know if the cultivars they do grow were developed there, in which case maybe they selected against the rust, which has been there for at least a hundred years as far as I recall. As you say, it can't be the climate since the wild species there get rust. Could it also perhaps be that in urban residential gardens there is some protection from wind blown spores from the wild areas, perhaps?

Edit: I should add that most wild daylilies in Japan are deciduous so the rust needs patrinia in order to return the following year - I don't know if that also applies to the cultivated daylilies but perhaps could also be a factor.