I live near Philadelphia. I have been having issues with my plants. I was very inexperienced and watered too much and planted too close.
This year I decided to tackle the problem with everything I could find. I used wood chips as mulch (did not mix it into the soil) about 2 inches deep and not touching the plants. I chose disease resistant plants and just planted cucumbers and tomatoes with very adequate spacing. I’ve gradually increased the soil nutrients with compost over the years because the soil was high in clay and had my soil tested and amended. I have a drip system that brings the water directly to each plant. I trimmed off the bottom leaves of the cucumber plants because I felt like it might be a soil born issue. I never water by hand but it does rain.
My tomatoes seem to be doing fine but my cucumbers are doing the same thing they’ve done every year for the past 3 years (I did not crop rotate). First the plants grows fine on the trellis. Then a few weeks after harvest begins light green then dried brown/yellow spots form on the bottom leaves and seem to work it’s way up. Eventually the leaves die but the plant continues to grow and produce cucumbers. The cucumbers don’t seem to be effected much except they seem to curve more often later in the season then the beginning of the season. No lesions. It seems to start on one plant and eventually moves to other plants.
Included are a few pictures of the plants, the leaves, underside of the leaves, and the cucumbers
Certified GKH Gardening Expert
It is very likely that there is just too much nutrients in the soil. The most common signs of this are nutrient burn holes, and misshapen fruit. It may have to decompose, and be used by the tomatoes quite a bit before cucumbers will be able to grow here. They can't quite handle a "hot" soil, so the only option will be to wait.
You could try flushing your soil with citric acid, but if you have never done this before, then it can be very easy to lock up your soil, making it useless.
This article will give you some more information: https://www.gardeningknowhow.com/edible/vegetables/cucumber/deformed-cucumbers.htm