Argentine ants are among the most destructive insects in your garden. They protect insects that damage your plants and spread diseases such as cucumber mosaic virus.
First, locate their nests which are usually under hard objects such as boards or bricks. Water, even just a small amount, causes them to flush out of their nest with eggs. Spray them with a safe insecticide.
Permethrin (synthetic) or pyrethrin (organic) are very effective and have residual protection. But these insecticides are harmful to many beneficial insects. Only use them on the ground and not on plants. Soapy water is somewhat effective but doesn’t have any residual protection. Let as many ants come out as possible before spraying.
Ant bait stations can be helpful. You can purchase these at most garden stores or make your own borate-based bait.
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