For the past several years our Cucumber plants have wilted in the mid summer...
For the past several years our Cucumber plants have wilted in the mid summer and then died. I can detect no insect infestations or mold. The fruit just shrivels up without evidence of rot
Baltimore County Maryland vegetables
From your question we are not clear if you mean the entire plant, just the fruits, or both.
If it is the entire plant, this would be bacterial wilt disease. Here is an info page on that from the Grow It Eat It portion of our website:
It is very common, and damaging, but there are ways to manage it for future crops which are detailed on the link above.