I don't know where you are, but March was very likely too late. It would have been in my zone 6. Maybe November was too early?

Lychee:

It does appear that your peach tree has curl. But what was the copper formulation you used, where did your purchase it, and how did you apply it? November and March should have been pretty good timing for dormant sprays where you live, which I believe, but cannot prove, is Brooklyn, New York.

There are significant differences between copper products sold on the consumer market, and differences in the way they are applied. The product called "Soap Shield" from Gardens Alive! for example, is almost useless, since it has a very low component of fixed copper. Where are your buying your dormant copper spray, and what is the brand name? And how are you applying it, with a pump-up sprayer, a hand sprayer, or what? What are the dilution instructions on the label or the insert of the product you are using? These are the kinds of details that make the difference between an effective and an ineffective dormant spray. It's not rocket science, but it is close.

The dormant copper product I am using is called Kocide, which is copper hydroxide, and it is very effective at eliminating overwintering fungi, including peach leaf curl. However, curl is usually most troublesome in climates with a slow spring warmup, and I have seen it only rarely here. I used to dormant spray with lime/sulphur, but found copper to be more effective and less trouble to apply. Lime/sulphur sprays, which are sold in liquid rather than dry form, tend to crystallize and clog the sprayer if kept more than one year.

When you are looking for advice on a fungicidal spray, it will always help to specify where you purchased it, the brand name, and what the ingredients are as listed on the front of the label.

Don Yellman, Great Falls, VA

Two winter seasons ago, it was horrible. I applied around 8 times of spray but it only helped a little. We had rains almost everyday during the winter, not the heavy rain, but nuisance drizzles that the fungi love to multiply in. I apply during the break in the rains, but then again it would rain the following day, so nothing was really effective.

I forgot to spray copper but then again the peach curl forgot my trees. So I didn't get them this time. It was actually one of our driest winter, so I didn't bother to spray, and true enough, out of several hundred thousand leaves on my peaches and nectarines, only about 5 of them have the curl.

One of the very good sprays is the lime-sulfur, aka, calcium polysulfide. But don't apply this on apricots. I would only use that in the dead winter. During leaf fall, which is around Thanksgiving in our area, I would apply kocide or copper sulfate, then around Christmas Day which is the dead winter time, I would apply either bordeaux mixture or lime sulfur, and then around super bowl time, I would apply kocide again. I would apply milder subsequent sprays during bloom time if there are rains during the bloom.

Don- I am in Brooklyn NY. i used bonide liquid copper spray- the label says it has 10% copper octonate and the equivalent of 1.8% metalic copper content. I used a pump spray. I dont recall the dilution instructions and I have since lost the lable, but I would have followed the instructions on the label concerning the dilution. So what do you think- should this have worked? do you have an alternative spray that you can recommend?

Lychee:

The Bonide liquid spray you are using may be intended primarily for use as a growing season fungicide. Peach leaf curl is best controlled by dormant applications of fungicides such as lime/sulphur or copper in much stronger formulations. The product I use for dormant spraying is called Kocide, but there are other brands that may work, and you may also choose to try lime/sulphur. You may have to do some online searching to find Kocide or other dormant copper products, since they are seldom sold at local nurseries or bigbox stores. Lime/sulphur is found more frequently.

I have a 16 oz. container of a Bonide liquid copper spray here that shows 49% active ingredients of active copper salts - metallic copper equivalent 4%. According to the insert, this product is recommended as a dormant spray for peaches at the rate of 7-10 teaspoonfuls/gallon, which works out to about 1 fluid ounce per gallon. Dormant application is recommended at leaf fall, and again in late dormant up to pink bud. This product, from the same distributor, appears to be at least twice as strong as the one you used, but is still inferior to Kocide in that department. The Bonide liquid copper spray is also extremely expensive. When I am dormant spraying, I tend to mix on the stronger side, and would use at least that much of this product. However, I would not ever use Kocide during the growing season, since it would severely burn the leaves, healthy or not.

It is unfortunate that you almost have to be a chemist to figure this stuff out, but it does appear the product you used was insuffiently strong to eliminate the curl when it should be eliminated. Once curl appears, it cannot be cured with any spray product. You have to stop it before it starts.

Don Yellman, Great Falls, VA

thanks Don. I'll try and get hold of Kocide. May I ask where you obtained your Kocide from?

lychee:

I got my Kocide from a California firm called Rosecare. But I had to buy a 20 lb. bag that cost me $80 plus shipping. The trick would be to find this stuff in smaller amounts, and I seem to recall someone mentioning that it is sold in consumer amounts by a firm someplace in the Carolinas. Unless someone volunteers a source here, I am afraid you will have to search it online.

Don Yellman, Great Falls, VA

Okay, here's from someone ignored here:

$27.99 for 3 lb bag plus SH

Here is a link that might be useful: Peaceful Valley Kocide

sorry- joe- really did not mean to ignore you. many thanks for the info and apologies again.

lychee, was just kidding. no harm done!

I found Kocide not to be effective last year when we had severe case of humidity due to constant rains up to the bloom time.

What I did then was to fertilize heavily with nitrogen and epsom salts and they recovered during the late summer. Now I have loaded trees with very few insignificant peach curls and I forgot to spray.

Anyway, Kocide can be effective if the concentration is proper. I have to dilute mine to control brown rot and twig blight and spray during the bloom, but the rains spread the PLC very extensively.

I am planning to use just Bordeaux mixture by preparing stock solutions. I cannot find cheap sources of powdered copper sulfate though. The Bordeaux works very well on Apricots for now. So I just want to handle one chem type at a time and will rotate them each year.

Nordox 75WG, Cuprous Oxide 12 pound bag for 80 bucks and that will treat 1.5 to 2.5 acres. I am waiting to see how effective this is, but I was told to apply it and it is supposed to be the latest thing. I'll let you all know.

I use Cook's Copper Oil Spray. I bought the bottle several years ago so I don't know if it is still available. It must be a dormant strength product.

The most significant thing I have found is that it needs to be applied several times during the winter to be the most effective. Also, it must have a few days after application before it rains. If it rains in the next day or two, it doesn't do much of any good. I have been led to believe that the pathogen is water-borne, and my experience seems to bear this out. Even spraying five or six times while dormant, I still sometimes get a slight infection. If I don't spray, I have a horrible infection.

Geraldo, do tell us about how Nordox works, the ads get me excited. I am concerned about how much copper I have to use (as an organic grower, copper is 80% of the key to tough disease control) so anything that gives you more mileage per molecule is a real win to me. I don't see any Internet supplier for us "little guys" yet though.

I now use Kocide via Peaceful Valley. I recently switched to lime-sulphur for my dormant sprays to minimize the amount of copper used, but am still using copper on the stone fruit. For my vinafera grapes, copper is the magic bullet during the growing season.

Scott

Yeh, I'll let you know later in the summer. You might have to remind me. I don't get too involved in this, I just spray what I am told to spray and when. They give "free" advice where I buy.
Seriously, if they tell people to spray the wrong thing it could severely impact their business. And believe me, they do get feedback. A lot of it, quickly, and sometimes vociferously. They sell products that cover tens of thousands of acres.

i found a slightly cheaper source for kocide-
$20 for 3lb bag and $10 shipping to NY.

Here is a link that might be useful: KOCIDE

Has anyone tried Liqui-Cop as a copper fungicidal spray? The label says it's an 8.0% metalic copper from copper ammonium complex. I bought it a few years back, never used it. It's supposed to be able to mix with a horticultural oil to make a dormancy spray.

One reason I believe synthetics are sometimes a better choice for the environment than "organics" is they are sometimes so much more affective, particularly for the hobbyists that doesn't have the time for multiple applications. A peach tree that doesn't bear peaches is a waste of space and means that somewhere else a little piece of forest must be removed from the planet (I put it like this to make a point even if it isn't necessarily a litteral reality). I find a single application of Bravo just before budswell to be quite affective in controlling peach leaf curl. Often a single application actually clears it up so thoroughly it doesn't return in subsequent years with no treatment. My observations are anecdotal of course but I invite others to go on-line and compare the research as far as relative efficacy of materials.

I sprayed my stone trees with kocide in early december but I would like to apply some bravo in February. Does anyone know an online source for Bravo500?

Damn, I go recommending a material and forgot that it's hard to get in smaller than commercial quantities. UAP has it in NY 845 795-2177. You could probably get them to UPS some to you but it would be enough for acres of peaches. It's not a real expensive product.

Wish I could just give you a little.

If anyone is looking for copper sulfate crystals for making bordeaux mixture, copper sulfate is commonly sold as a drain cleaner to kill roots in sewer drains. WARNING, READ THE LABEL, THE INGREDIENTS ONLY MUST SAY COPPER SULFATE, NOTHING MORE, NOTHING LESS.

Harvestman.

Do you think you could mail me some Bravo. I would gladly pay for the postage and for the bravo.
please email me at grunsfeld at gmail.com and let me know.
many thanks.

1. A quick Google search turns up an EPA notice, dated December 9, 1999, advising of a receipt of requests to voluntarily cancel "certain pesticide registrations". The notice goes on to state that unless the requests are withdrawn by the registrants, deregistration would become effective on June 26, 2000. A fair number of Bravo formulations are included on the list. Of course, cancelling the registration for use on one crop does not necessarily mean it is canceled for other uses. If Harvestman is still able to buy Bravo, it is obviously being sold.
2. Of greater interest is the presence on the list of several versions of Daconil 2787, for which the active chemical agent is listed as -- get ready for this -- Tetrachloroisophthalonitrile. That would be a good one for the spelling bee. This is the same chemical ingredient shown for most forumulations of Bravo, suggesting to me that the two products may be chemically identical.
3. I have noticed that Daconil 2787, which used to be commonly available at my local consumer sources, has not been seen on the shelves for at least 5-6 years. So it may be that Daconil 2787, the consumer version of Bravo, has been withdrawn from the market, and Bravo is available for sale only to "registered" users of ag chemicals, which is the case with a good number of other pesticides and fungicides that can legally be sold only to commercial operators.
4. This is all very confusing business, and I am sure I will never figure it all out, but the clear facts indicate that more and more chemicals once available to backyard orchardists are now gone. I don't deny that this may have some environmental benefits, but is does limit the flexibility of the backyard orchardist.
5. I still have a quart of Daconil 2787, but this fungicide was never very effective for me, which is why I stopped using it. However, I don't have much pressure from peach leaf curl here either. Bacterial spot is a much bigger bugaboo on my peaches.

Don Yellman, Great Falls, VA

Much as I love Lychees also that would be indiscreet and could cost me my license. It's not restricted so if I got UAP to fax me a label to send with it it might be legal so let me look into it. email haigal@aol

A Google search turned up an eBay source for "Bravo", with 26% Tetrachloroisophthalonitrile, under the name Bonide Fung-onil. Not too expensive, as chemicals go.

alta- was that a curren auction- i could not find it- can you post the link to the auction?

harvestman- my email to you was returned undelivered- was there a typo in your email address? perhaps you can email me at grunsfeld at gmail

Lycheeluva, a search for "Fungicide Bravo" turned it up.

Here is a link that might be useful: Bonide Fungonil (Bravo)

From the latest tip of one of CRFG chairman, I will be trying out TEA TREE OIL. He told me it is very effective organic fungicide against Peach Leaf Curl when applied a week before buds begin to swell. The added bonus is that it can kill insect eggs and other over-wintering insects that happen to be on the tree during application.

Use about 2 tbsp per gallon. The Tea Tree Oil can get expensive, so is not good for commercial growers. It would be my first time to try the tea tree oil this coming season. I still have to apply truly dormant stage (all leaves fallen off, mid-winter, tree truly dormant) copper (strongest concentration) sometime next week when the rains have died down. After that, application of tea tree oil before the budswell which should be around early February, but depends on the weather pattern.

I love these "tips". How bout a little research backup before someone looses a crop on an experiment. Peach leaf curl is an unpredictable disease so anecdotal observation is not going to be a very useful method of evaluation.

Lychee, did you get my e-mail?

Chlorothalonil aka Bravo, Echo, Applause, and Concorde is not a restricted material in NY which is one of the most restrictive states, 2nd to only CA I reckon. Or at least it wasn't as of the publishing of the Cornell 2007 Tree Fruit Pest Managment guidelines.

It's use as a brown-rot control for peaches is limited to early application which doesn't matter to me either because I agree with Don that there are much better materials for this. To my knowledge however it is still supposed to be the most affective treatment for peach leaf curl and for black-knot on plums which is what I use it for.

I don't find peach leaf curl to usually be a very persistant problem if trees are pruned open enough and they recieve enough direct sunlight.

I know from experience that when there are persistent rains you can continually spray for peach leaf curl but even with persistent spraying you may not prevent peach leaf curl.

We use Koicide commercially and have good success with it. I have a restricted materials permit in California and most of the fungicides I use are unrestricted materials.

What amount of Kocide should I use per gallon during the dormant season to control for brown rot?

If Kocide is antibacterial, does it help against fireblight?

JoeReal: How much do you dilute your Kocide when you spray it during the growing season? I assume you are doing it at petal fall or thereabouts.

Regards,

Nimzo

I'm using kocide to control fireblight. 1 tsp per gallon. Apply every 4 days or every week (depends if windy or not) the entire blooming period. Apply directly on the blooms, so a lot quicker and don't need a lot. It works great on fireblight. I stop spraying on susceptible cultivars after petal fall.

Home Depot in Islip NY has Chlorothalonil. It comes in a green
1 pt. container, $13.94. Made by Ortho and says Garden Disease Control, stops and prevents over 130 Diseases.

I have Bonide Liquid Copper that I was going to use for dormant sprays, Peach leaf curl, Brown rot. The copper equivalent was only 1.8%. Quite low compared to the Kocide. I'll save the organic copper for fireblight spraying if I get any.

Nimzo, Kocide lists on the product label that it can be used to control fireblight on pears. Read your label to see what is recommended to control fireblight. My Koicide label is close to the interval Joe is spraying. My label says something like every 3 days during bloom. If you go more than a few days between sprays during bloom, you risk your trees getting blight.

My experience with Fireblight on my pears here in Central CA is that the greatest risk to get fireblight is during the bloom stage. One the blooms are gone and we get farther into spring, it seems for me anyway the risk greatly diminishes.