Colorado Potato Beetle (Leptinotarsa decemlineata) overwinters as an adult in the soil or in sheltered areas near previous host crops. Adults emerge in spring and move to potatoes, eggplants and other plants in the nightshade family. Females lay clusters of bright yellow-orange eggs on the undersides of leaves. The eggs hatch into reddish larvae, which feed heavily before dropping to the soil to pupate.

Both adults and larvae chew foliage, producing irregular holes along leaf edges and eventually throughout the leaf. Heavy infestations can completely strip a plant of foliage. Eggplant is particularly vulnerable when plants are young and around flowering.

How to Fix It
Check plants frequently: Inspect leaves, especially the undersides, for adults, larvae and clusters of orange eggs.
Destroy the eggs: Crush or remove egg masses before they hatch.
Hand-pick beetles and larvae: Drop them into soapy water. This is effective in a home garden when started early.
Rotate crops: Grow eggplant and potatoes away from where potatoes, eggplants or other susceptible crops grew the previous year. Rotation is particularly useful because many overwintered adults initially travel on foot to find new host plants.
Use straw mulch: A thick layer of straw can reduce the number of beetles reaching plants and also provides habitat for some predators.
Remove volunteers: Eliminate volunteer potatoes and other nearby host plants that can provide food for emerging beetles.
Keep checking: Colorado potato beetles are notorious for developing insecticide resistance, so early detection and physical control are especially useful in a home garden.