It seems each year we do battle with cucumber beetles on our cucumbers and squash. We always notice them late and the have to result to drastic measures to control them.
Here is how to recognize these pests and some different ways of controlling them.
These beetles are very harmful to young cucurbits plants. They are identified by their spotted, striped and banded yellow and black colors. The beetles will start feeding on young plants as soon as they emerge. They can kill the plants or cause very slow growth. Beetles will be around through the full growing season and will eat all parts of the plant, flower and fruit.
Cucumber Beetles will also transmit bacterial wilt. This disease will survive the winter in the intestines of the beetles and is spread when the beetles eats on a plant. Infected plants will eventually certainly wilt and die after a time.
Cucumber Beetles larvae will bore into the roots and stems of cucumber plants.
The yellowish-green adult posted cucumber beetle has 11 black spots and a black head with black antennae. They will be about ¾ of an inch long when grown.
The yellow striped cucumber beetle has three black strips and is about 1/5 of an inch long.
The banded cucumber beetle is yellowish green and has three bright green stripes across the wing covers.
In the home garden we can use some control measures to help control the pest. The use of fabric row covers gives us an effective barrier to keep the insect away from the young plants. Be sure and uncover the plants during flowering to ad pollination. Handpicking the beetles to remove them is another effective option but it will be time-consuming. Cucumber beetles do have several natural predators and parasites that will help control them.
Now that we have identified our pest as cucumber beetles how do we control them?
The natural options are Pyrethrin and Neem oil extract.
Pyrethrins are organic compounds derived from Chrysanthemum cinerarifolium that target the nervous systems of insects.
Neem oil extract is a naturally occurring pesticide that is found in the seeds from the neem tree. It is yellow brown and has a bitter taste with a garlic/sulfur smell. As with all insecticide please read and follow all direction on the label of the product.
If you want to use a contact pesticide then the best for the cucumber beetle will contain one of the following as it active ingredient: Carbaryl, Bifenthrin, Cyhalothrin, Cyfluthrin. Any of these works well. As with all insecticide please read and follow all direction on the label of the product.