Answer: Based on your description it sounds like the plants have mildew or some other fungal infection. This can be caused by excess humidity or damp foliage, poor air circulation, an oversupply of nitorgen, or sometimes, it just happens. Since it is so early in the season, I would suggest you discard these and try again outside. There is still plenty of time and cucumbers can be planted directly in the ground where you want them to grow.
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