Copper is one of the most widely used bactericides available. It is a strong and viable tool for managing bacteria and fungi in crops including fruits, vegetables, hops and tree nuts.
Used best in a preventative manner, copper can be a highly economical and effective option for safeguarding and protecting your specialty crops, says Bob Bruss, Director of Technical Services for Crop Protection for Nufarm.
Understanding copper’s unique properties
“Bacterial diseases are usually most prevalent when it’s wet,” Bruss says. “That’s also when you can get copper working better.”
Effective copper products should achieve preventative or early control of key diseases including bacterial canker, blights, leaf spot and more.
“Copper ions are strongly charged and bound to each other. The trick is, you want to get those copper ions inside of a bacterial cell, or inside a germinating spore.”
He says some forms of copper are very water soluble and can get into the plant too quickly, causing copper burn.
“You want a product and application method that will release all of the copper but will do so slowly to minimize injury.”
Bruss emphasizes using copper as a preventative protectant measure, so the plant can be safeguarded against bacterial or fungal spores as they develop.
Conditions and timing are key
“Weather is the single most important factor when it comes to the value and performance of your copper product”, Bruss says. “You need moisture present for copper ions to be available for disease control. In intermittent wet and dry conditions, sufficient moisture may be available for diseases to develop, but it is important to use a quality copper formulation that readily releases soluble ions.”
Early applications will often be made in high-value crops such as apples and grapes, as producers are trying to catch the diseases early and prevent infection before they have to start using other fungicides. In many cases, early application is how you will get the most out of your copper, as it works better on germinating spores instead of when the disease is farther along, Bruss says.
Nufarm has a comprehensive line-up of copper fungicides. Go to NufarmPoint.com and click on the TNVV tab to find the full copper fungicide article and product information.