Colorado Potato Beetle

The Colorado Potato Beetle (CPB), Leptinotarsa decemlineata, is native to North America. The CPB was originally a western pest, hence its name, but it moved east with potato crops. It feeds on the leaves of the potato plant and can completely defoliate an entire crop, if left uncontrolled. Although potatoes are its favorite food, it will also feed on eggplant, tomatoes, peppers, tabacco petunias and sometimes even cabbage.
It is the larva of the Colorado Potato Beetle that does the damage to vegetable plants. The larva feed on the leaves of host plants, weakening and eventually killing the plant, if not treated.

The adult CPB overwinters about a foot below the soil surface. The adults emerge in late spring, find a nice potato patch or garden, mate and lay their eggs on the undersides of leaves. In cold climates, there is only one Colorado potato beetle generation per year. In warmer areas there can be up to three generations. A single female beetle can lay up to 500 eggs.

The best control of Colorado Potato Beetle comes from keeping them out in the first place. Mulching with wheat or rye straw seems to hinder the beetle’s ability to find potato plantings and it has the added advantage of being an attraction for CPB predetors like lady beetles and green lacewings. Cover susceptible crops with a floating row cover in late spring will protect the plants from egg laying female CPB. If you have a small garden or crop, you can monitor the undersides of leaves and scrap off or squish CPB eggs when they first appear. Rotating your affected crops can help lessen the population of CPB, but it won’t get rid of them entirely.