Colorado Potato Beetle

Adults are yellow convex beeles, about 1/3 inch long. They are maked with black stripes and an orange head covering. The eggs are bright yellow and are laid on the undersides of leaves. Grubs are plump and red, with black spots and a black head. Both adultss and larvae chew foilage. One or two generations occur every year. The beetles overwinter in the adult stage. Adults emerge from soil in late April to early May.

Symptoms include defoliated plants with skeletonized leaves.

Vulnerable plants eggplants, potatoes, and tomatoes. They can pester just about any vegetable though, but they prefer the above.

Best control methods are handpicking the first arrivals in spring and using pyrethrum spray if they get out of hand. apply a heavy organic mulch because the beetles cannot emerge through the mulch if it's heavy enough.

Plant a trap crop of black nightshade. Locate it within 10-15 feet of the crop threatened. Once heavily infested, pull of plants and destroy!.

DO NOT use bug juice spray against the beetles because it is toxic to potato plants.

Instead use, Bt. Use 2 aplications of pyrethrum 3-4 days apart. Rotenone can be used as a dust or diluted with water for spraying. it can be used in two concentration-1% for most and 5% for hard to kill bugs such as this beetle. It can be used up to 24 hours before harvest. Remember, this one also kills beneficials.

Or try a really fun way to kill them....sprinkle cornmeal or bran over plants. The beetles eat this stuff like mad. Once inside the beetle, it expands and the beetles explode! Woohoo! (I may be sick in the head for enjoying a good beetle blast or a good horned tomato worm scissor cutting.)

Be sure to cleanup debris in fall. Cultivate the completely bare soil to 6-8 inches deep. About 2 weeks later rake the soil and leave it bare for a few more days. Birds enjoy digging in that soil for the pest. Plant a cover crop or lay a 4 inch thick mulch. Two weeks before planting, give the soil another shallow raking or cultivation to about 2" deep. This gives birds the opportunity to finish off some of the ones that survived the first round.

Use Diatemaceous earth completely on all plant parts. This can be tedious after a few days when you have to reapply and have a very large garden.

Go To Page: 1 2