There are three types of Cucumber Beetles, the two most common are the Striped and Spotted.
The third type is a tropical species and is found mostly in southern states, it is the Banded Cucumber Beetle.
The adult beetles feed on the leaves and flowers of cucurbits such as; cucumber, squash, melons and pumpkin.
They can also feed on the rind late in the season, reducing marketability.
The larvae feed on the roots of these plants.
The main problem with cucumber beetle is the fact that it is the vector, (it spreads) a bacterium called Cucumber Bacterial Wilt.
This bacterium has no known cure, so when the plant gets this bacterium, the recommendation is to immediately remove the plant.
If you don’t remove the plant it will spread to other plants and eventually infect all of the other plants in your garden.
The first symptom you have this bacterium is, suddenly a vine will wilt, and the rest of the plant remains looking fine.
If you suspect you have bacterial wilt, take a sharp knife and cut the vine, rub the two ends together and slowly pull apart. If there is a white, stringy substance, not clear, you have the bacteria. Note, if the substance is clear and snaps back when you separate the two ends, you may have squash vine borer and that can be treated so don’t be too hasty to remove plants.
The key to avoid the bacteria is to control the cucumber beetles.
The first line of defense is to use floating row covers and such to exclude the early adults from the first feedings and laying eggs.near the plants.
Only leave the cover on until blooming begins.
The best, most effective chemical control is the use of NG Spinosad or NG Spinosad Soap. Spinosad is translaminar, so it will penetrate the leaf and be inside the plant when the beetles feed. Spinosad Soap has this ability, but also will knock the adults off the plant in minutes.
I would spray the Spinosad Soap on all my plants immediately if I thought I had the bacterial wilt. you will get fast action and prevent it from spreading to uninfected plants.
Oh yes, these are OMRI listed for organic gardening.
Hard chemistry control includes HY Lawn, Garden, Pet & Livestock Spray or HY Garden, Pet & Livestock Dust.
For a dust that is more persistent and doesn’t need to be applied every time it rains or you water, use HY Multi-Use Dust.
For all controls, try to apply below the leaves and along the vines and spray in morning or evening.