Use a shop vac. It is the only safe thing I found to be very effective.

Thank you, how often do you use the vac?

The only thing that works for me is covering the seedlings until they flower. I'm an organic grower but even the conventional farms in my area often use row covers, because one bite from a beetle can infect with bacterial wilt and take down the whole plant. I've never been able to control with sprays, but I won't spray once the plant has flowers. I keep bees and even organic sprays such as neem and Pyganic will kill bees.

I succession plant as well; when a row cover comes off I've got another batch of seedlings ready to plant. I do this all season long. I've even dabbled with hand pollinating, but that's complete insanity. Just using row covers until the plants flower is enough for me to have a constant supply of cukes. I'm normally the only grower at my market with cucumbers at the end of the summer. I think that growing cucumbers is much harder than most people realize.

Vacuum every morning until they are gone. I cover until heavy flowering but one year we had a cucumber beetle outbreak and I learned to vac. The bees were not sucked up but the beetles were and no beneficials were harmed.

I grow cukes vertically in a hoophouse and covering is not an option. I spray with Pyganic (organic certified) and it does the job. I also keep bees so I am uber sensitive to Pyganics effects. I like Pyganic because it has zero residual effect. And no waiting period for harvest. It is made from Chrysanthemums. I spray early in the morning or late at night when there isn't any bee activity. It is expensive but can be used for a lot of other bugs. I spray for squash vine bore with it too.

Thank you for all the feedback. I have a plan now. I am using the hand held vac twice a day. They seem to be decreasing in numbers. I have started another planting, and I am going to check some places for pyganic to have it on hand in case they come back and for next year. The literature says they will lay their eggs and hatch out in 30 days for another round. If so I will be ready. Now just to keep my fingers crossed that the plants I have are not infected. I agree, cukes are harder to raise than many people realize. When they are good they are very good but when there is a problem it is bad.

Careful with Pyganic ... it will kill ALL insects so make sure you don't wipe out your pollinators trying to protect the crop. The worker applying it needs protective gear.

http://www.valent.com/Data/Labels/PyGanic_1_4_MSDS%20Rev%207.pdf

CAUTION. Harmful if swallowed or absorbed through the skin. Avoid contact with skin, eyes, and clothing. Avoid breathing vapors or spray mists of this product. Prolonged or frequently repeated skin contact may cause allergic reactions in some individuals.

Applicators and other handlers must wear a long-sleeved shirt and long-pants, chemical-resistant gloves such as Barrier Laminate, Nitrile Rubber, Neoprene Rubber or Viton, shoes and socks.