Homepage » Forums » Plants, Climates and Soils » copper sulfate spray for fruit trees (bordeaux mix/ bouillie bordelaise)

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    Here in France we are *constantly* told to spray with copper sulfate: our old fruit trees, our new ones. . grave vines, strawberries, tomato. . . every few weeks in some cases.

    This stuff is an antifungal which is permitted in organic agriculture but which obviously is seems to me to not be picky about which fungus it kills and I’ve heard it can dammage earth womrs and other soil dwellers.

    I have found that the French are typically rather reasonable when it comes to spraying things all over their backyard gardens, so I’m surprised when all the people who really seem to know what they’re doing keep telling me to use copper sulfate. In addition, my husband keeps hearing from his brother that *must* spray our fruit trees or else.

    I don’t want to use it on our garden anymore–it was used here regularly by the old owners. so my questions are 1. Am I just being stubborn–a case of a less experienced gardener not wanting to take lessons from the more experienced crowd? and 2. Is there a protocol for rehabing an area that was formerly treated with this stuff–I mean, if I take my older trees off it ‘cold turkey’ and they don’t have good soil life underneath, am I going to have trouble?



    It is used commercially in our area but I have had personal experience with it only for mango trees in south Florida because they easily get a fungus called anthracnose on the leaves and fruit which if not controlled can kill a tree and make the fruit inedible. Some varieties of mangoes get it worse than others. I would suggest planting a variety of a particular fruit that is first of all resistant to the types of fungus that occur in your area. As a matter of fact commercial Mango farmers do not exist any longer in south Florida because it is easier and less costly to grow mangoes in South America where they have fewer problems with fungus. I don’t know the rules for organics but it will be interesting to find out if they can use copper sulfate. If so then I will not eat organic produce using it especially fruit like grapes, strawberries, and tomatoes. Of course no one eats the skin of a Mango but I think really something better should be used there as well. I have been away from the fruit tree orchards for many years but now that I am back I will experiment with alternative fungicides and pesticides that are safe like Neem. I know concentrated metals absorbed through the skin are not healthy and the link below sites disease in orchard workers exposed to copper sulfate. Thanks for your post. I found this facts sheet at the following link:



    Sheesh! Thanks for the reply and the link. I like having university grade evidence to back up my arguments. Just what it does to the soil life is alarming enough but it’s also kind of alarming to know that it’s so irritating to orchard workers or that there could be links to birth defects.

    I think it’s funny how people sort of brush me off when I express a concern about copper sulfate (among other things). The number of times I’ve been told, “Oh, it’s considered organic.” Sigh.

    By the way, no wonder the dirt under our fruit trees is in such poor shape. It was treated for about 25 years by this stuff by the previous owners. And it’s not like you just apply it once a year–usually it’s several applications a season. . .



    I would recommend only using it to treat an infection – don’t use it as a preventative. if plants continuously get infected then pick different varieties as advised above.

    We had to use it on an apricot that had shot hole (I think it was infected when we bought it) otherwise we would have lost the tree – once we cleared the infection we didn’t have to use it again. we also didn’t spray when the plant was in fruit so didn’t have any problems with high metal levels in the fruit (I even had a test done to check because I was curious)…



    Illiah, I think that I heard that spraying stone fruits after the buds have opened in the spring actually kills them–so that you always have to do it when they’re dormant?? We’ve got a sick apricot too, but the fruit’s already on it and I’m pregnant–and given the info on the link from Talinmark above, I’m not having that stuff sprayed around here until the baby arrives safe and sound!

    But I agree that a one-time use seems a lot more sane than several times in both spring and fall.



    Wow, how people just believe what the seller is telling them. I used to live in Belgium, and people went to the doktor for every little thing, and swallowed anything the doktor gave them.

    As a child I didn’t want to wear sunscrean. It didn’t feel safe or logical to me, neither did fluoride in the toothpaste. They even gave me fluoride treatments, and totally ruined my teeth with it. I have fluorosis now. I told them it couldn’t be any good, and they didn’t listen. What would a child know?

    Well one fact that I know, and to me feels very permacultural as well, is that a child follows it’s gut. And you still did when it came to copper sulfate. It didn’t feel right, the name didn’t sound right. Yes, it’s biological, the salesman was probably right… but the next question is; is it natural? If fruit trees really needed it, wouldn’t it be supplied by rainfall? Like sunscrean isn’t natural, fluoride isn’t (it would be in your food if you needed it), driving on bio-gas isn’t natural, processed biological food isn’t natural… I could go on and on.

    Keep following your gut on these things. Hope you get your plants and soil back to normal. And thank you for teaching me about copper sulfate. 🙂



    There’s a product out there called actinovate which is a natural beneficial bacteria that is applied as a foliar treatment. It may or may not help with fungal problems. There’s also info out there about applying raw milk as a foliar treatment which has shown to be very beneficial for a number of reasons. I’m not sure what relationship bacteria has with fungi but maybe occupying the real estate of your plants with the good stuff, will crowd out and out compete the bad? I hope that helps.

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