Are you growing potatoes, eggplants, peppers, or tomatoes in your garden. If so, now is a good time to check for the presence of Colorado potato beetles. Both the adults and larvae feed on these plants. Feeding can be severe and can impact production of your vegetables. These beetles have one to two generations a year and are seen from spring until harvest.
|Colorado potato beetle larvae on eggplant. |
Photo Jeffrey Hahn, UMN Ext
There are several options for managing Colorado potato beetles. Handpicking is an option as long as your garden is not too large and you have the time to remove them on a regularly basis. Spinosad is a low impact insecticide that is effective against Colorado potato beetles and importantly there is no known resistance by these beetles to it.
Traditional insecticides such as carbaryl (Sevin) and permethrin are generally not effective as most populations of Colorado potato beetles have developed resistance to it. It is possible that some relatively newer pyrethroids, such as lambda cyhalothrin or cyfluthrin can help to manage these beetles. However, if sprays don't seem to be affecting them, discontinue their use and switch to another management method.
For more information see Colorado potato beetles in home gardens.