This old thread may help you out with your question:

http://forums2.gardenweb.com/forums/load/organic/msg061432466681.html

No I have not, but below is an interesting link on it:

Also, I was at a garden seminar 2 years ago where the featured speaker was Jeff Gilman, a U of MN associate professor of hort. & author of "THE TRUTH ABOUT ORGANIC GARDENING". He reported that this was one of the organic methods that showed some good results. Here is a link to a nespaper article by him on the subject: (sorry don't know how to post 2 links in one response, so you'll have to cut & paste this one to see it)

http://www.startribune.com/lifestyle/homegarden/19284929.html?location_refer=Homepage

Here is a link that might be useful: Hort. Myths link

Thank you both.

I've tried it. It doesn't work.

But you can end up with a sour rose bush.

Title: "Powdery mildew control on apple and rose using milk fat and soybean oil emulsions"

Authors: A. AH CHEE (1), K. V. Wurms (1)
(1) HortResearch

Published In: Phytopathology 96:S4
http://apsjournals.apsnet.org/doi/pdf/10.1094/PHYTO.2006.96.6.S1

Abstract: "Powdery mildew (PM) is a serious fungal disease in a wide range of horticultural crops that can adversely affect yield quantity and quality. This paper describes the potential of milk fat and soybean oil emulsions to control apple PM (Podosphaera leucotricha) on the cultivar ÂRoyal gala and rose PM (Sphaerotheca pannosa var. rosae) on the cultivar ÂSaharaÂ. Potted plants were kept under controlled environment conditions and subjected to weekly sprays of the two emulsions along with fungicide, unsprayed and water control treatments. In apple seedlings, the milk fat and soybean oil emulsions significantly reduced PM after 7 to 8 weeks, to an average infection of

Here is a link that might be useful: link for above

Cornell formula may be more effective, and your garden won't smell like sour milk.

sock12345, if you want a 100% cure for powdery mildew try 1/4 teaspoon of Greencure mixed in with 1 Tablespoon of a pure fish oil foliar spray like DrammaticK or Neptune in one quart of water.To make sure this stirs evenly make sure you apply the Greencure first until it dissolves completely in the water. Then add the fish oil. It will get rid of all traces of powdery mildew within seconds. The effect is instant and complete! Last year my Lincolns were powdery mildew magnets, but when I applied this to my roses this year, all powdery mildew immediately vanished, never to be seen in my garden again. Powdery mildew hates this Greencure/fish oil mix and will choke and die on contact with this stuff.

Forget about this usage for milk. Milk, baking soda, tobacco juice and all he rest of the old wives' tales and home remedies will not solve your problems. If you apply this material, the first rain shower will wash it off, and you will have to do it again, and again, and again ad nauseum. As far as I know, after forty years with roses, the only remedy for Mildew is a chemical one, and that's the bottom line. Being organic is all the rage today, but it is not a universal panacea.

That really depends on where you live as to whether or not it will work for you. If you live down south in a constant humid climate, then probably going to have to do it again and again, but when you get some humid times and PM occurs, those natural remedies do the trick, and before you know it the weather is dry again.

lol -- Maybe the milk is good if you dilute it with chemical fungicide?

I am not giving the link for this abstract as my virus checker gave a warning for it. Here is the abstract:

Title: Mode of action of milk and whey in the control of grapevine powdery mildew

Authors: P. Crisp(A),(D), T. J. Wicks(B), G. Troup(C) and E. S. Scott(A)

Authors affiliation: (A)School of Agriculture, Food and Wine, University of Adelaide, Waite Campus, PMB 1,
Glen Osmond, SA 5064, Australia.
(B)South Australian Research and Development Institute, GPO Box 397, Adelaide, SA 5001, Australia.
(C)Faculty of Engineering, School of Physics and Materials Engineering, Monash University, Vic. 3800, Australia.
(D)Corresponding author. Email: peter.crisp@adelaide.edu.au

Published in: Australasian Plant Pathology, 2006, 35, pages 487Â493.

Abstract: "Grapevine powdery mildew, caused by the fungus Erysiphe (Uncinula) necator, is a major disease affecting grape yield and quality worldwide. In conventional vineyards, the disease is controlled mainly by regular applications of sulfur and synthetic fungicides and, in organic agriculture, by sulfur and botanical and mineral oils.
Research has identified milk and whey as potential replacements for synthetic fungicides and sulfur in the control of powdery mildew. Electron spin resonance and scanning electron microscopy were used to investigate the possible mode or modes of action of milk and whey in the control of powdery mildew. Electron spin resonance experiments showed that various components of milk produced oxygen radicals in natural light, which may have contributed to the reduction of severity of powdery mildew on treated leaves. Milk and whey caused the hyphae of E. necator to collapse and damaged conidia within 24 h of treatment. Hydrogen peroxide, applied as a source of free radicals, also caused collapse of the hyphae of E. necator but did not damage conidia, and appeared to stimulate germination. Lactoferrin (an antimicrobial component of milk) ruptured conidia, but damage to hyphae was not evident until 48 h after treatment. The results support the hypothesis that free radical production and the action of lactoferrin are associated with the control of powdery mildew by milk."

A couple of points about this thread.

1. The abstract says organic farmers control PM with "sulfur and. . .oils." Yes, but sulfur and oil at the same time will defoliate roses. Their use should be separated by some weeks. I would also be concerned about sulfur and fatty milk at the same time.

2. Contrary to one post here, organic remedies such as sulfur, oil, potassium bicarbonate, Cornell mixture, and (apparently) milk are highly effective against PM. Against blackspot they are less effective than synthetic fungicides, but some can provide satisfactory control in many circumstances.

3. 30% milk solution sounds like an expensive way to control PM. Other organic materials would be much cheaper and equally effective.

4. PM is not much of a problem in the South. The worst area is coastal California.

Of historical (1915) interest. Please note: "Casein or milk gives increased adhesion to leaves." It now appears that milk was helping fight the mildew.

Title: The use of sprays rich in copper.

Author: Rabate, E.

Published in: Revue de Viticulture (1915), 42 377-81.

Abstract: "Gayon and Millardet have shown that 20-30 mg. CuSO4 per 100 liters of water prevent growth of zo.ovrddot.ospores of Mildew (of vines). R. recommends the following Denig`e test for small amts. of Cu in soln. To 1 cc. powdered KBr add 1 cc. H2O and shake till in soln. Then add to the cold soln. 2-3 cc. pure K2SO4. To test for small amts. Cu, evap. 2-3 cc. of suspected soln. in an evapg. dish. To the residue add a drop of the above reagent. Cu is indicated by rose or carmine color. The reaction is specific. Com. sprays should be so tested because they are often colored with methylene blue and contain no Cu in soln. Molasses or glycerol added to neutral Bordeaux spray gives a larger amt. of Cu in soln. Casein or milk gives increased adhesion to leaves. R. recommends the following formula: 250 g. CuSO4 added just before use, 250 g. NH4OH, 60-80 g. casein dissolved in H2O with sufficient CaO, 1 kg. molasses. all made up to one hecto."

Yikes, I missed out on the followups of this thread. I completely disagree with Roseman in terms of Powdery Mildew! because I've seen with my own eyes how fast PM disappears with just one spritz of Greencure and fish foliar spray combined.

You can visually see the PM shrivel and disappear right away! within seconds. Just try it, I really urge this. But it's crucial to get the right fish foliar spray, the one that uses pure/non-processed fish oils such as DrammaticK.

The only thing that is "ad nauseum" as Roseman says is the organic battle against BS when you have a battle of rains and flooding catastrophes in one's area. With BS all organics fail with too much climate pressure as what I have mentioned. The only supposedly "organic" thing that is very effective is the borderline sulfur/copper compounds that have been used for decades, but this is harmful to earthworms and microorganisms in the soil after years and years of heavy-duty usage.

Lol -- organics work just fine against blackspot here in California, where the blackspot pressure is really light. I've seen it here once or twice and if you whistle at it, it goes away. But mildew, that's a whole different story. Nothing organic will work here in mildew central -- believe me, I've tried them all. For the folk who don't really have much mildew to be making claims that organics work, such as "if you want a 100% cure for powdery mildew try 1/4 teaspoon of Greencure mixed with . . . in one quart of water," or for that matter "30% solution of milk" . . . Sorry, that just borders on specious.

Last year, some of my rose bushes were totally white with PM, so I tried 2% milk (undiluted) and it worked amazingly well! It had been a very dry summer and the milk residue had lasted upon the foliage and I later had only needed to treat some of the new growth.

Terry

This spring I also tried 50/50 skim milk & water on three of my roses. Two of them only had the beginnings of PM, and it cleared up completely with two sprays, 5 or 6 days apart. The third rose, Felicite Parmentier, a severe case, improved but not completely. So, for me, it seems to work if the PM is not too far advanced. It could be coincidence, change in weather conditions, who knows? I will definitely try it again if needed. Much more trial is required. I used milk that had expired, by the way, so no extra expense. Obviously, it's a very regional thing, as are all disease control methods. I can't imagine having to deal with a garden FULL of mildew...or blackspot. I consider myself very lucky.

Judith

ugh, it's not one quart water, you need to have both!!!! the fish oil and Greencure combined in the same application. You can't isolate the 2 ingredients!!!! people don't combine both, it was something that I personally experimented with. It does kill the PM right away! Don't knock it until you've tried it because you've never tried combining both ingredients in the same solution. PM does shrivel and die on immediate contact with the combination.

And it's not specious because I see the PM dissolve right away with my own eyes. The effect was instant.

Why the fish oil/Greencure combo (mixed together) is so effective is probably because the salts and sodium from the fish oils helps smother and kill the PM plus it sticks to the leaves real good (the salt component) and the Greencure has long been known to help control the PM because it wacks out the PMs PH level. So having both in the same application nukes/roasts the PM.

When I did use Greencure by itself, it took much longer to affect the PM, and the PM always resurfaced eventually. Never with the Greencure/fish oil combo.