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Liquid Copper Fungicide #679123 - Ask Extension


Liquid Copper Fungicide #679123

Asked January 13, 2021, 6:59 PM EST

Hi, I'm from San Diego. To prevent against leaf curl, I treated both my nectarine and peach trees (twice, one week apart) with Bonide liquid copper fungicide. Both trees had severe leaf curl this past year and the fruit set was poor. Near the nectarine tree is potted parsley and scallions. When I sprayed the trees, some of the fungicide drifted over to the parsley and scallions. Will this damage the parsley and scallions? Will it make them dangerous to eat? On another note, if the nectarine and the peach tree have the leaf curl again this growing season, should I replace the trees? Would it be worth it to also spray these trees with Neem Oil? Many thanks, Bruce Belsky

Alcona County Michigan

Expert Response

Hello Bruce,

The label for the product you mentioned, bonide liquid copper fungicide, is online and I went and read the label. The label indicates that this product is safe to use on the onion family, parsley and chives. Of course I would wash anything before consuming it. Please see the label on your product under the ‘vegetables’ listing. Here is the label on the Bonide website

Since your herbs and vegetables are in containers, in future I would move them out-of-the-way before spraying your trees again with anything. That way you can control how much fungicide or other product is reaching your edible plants in containers.

Have you also consulted with your San Diego County Extension? They will have region specific information, different from what we experience here in Michigan—

I am referring the fruit tree questions to a fruit expert to help you with that part of your question.

Regards, Laura.

Laura Sheffer Replied January 13, 2021, 7:30 PM EST

Peach leaf curl infections can occur from the first hint of bud swelling until temperatures are too warm and leaves are more than half expanded.  The puzzling sporadic nature of this disease is due to a rather precise combination of temperature and moisture needed for infection. Peach leaf curl infections occur in the spring when wetting periods over 10 hours occur under cool conditions (46°F to 53°F), with rainfall greater than 0.5 inch.  So it is possible that you are getting the disease because buds were starting to swell and the weather conditions were conducive before you got your spray on.  

The following is a link to an article I wrote about this disease.

So, put your first copper spray on before any bud swelling is seen and another one at least 2 weeks later.  Neem oil is primarily an insecticide, so not helpful for this disease. 

William Shane Replied January 13, 2021, 9:34 PM EST

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