Answer: Cucumbers are succeptible to a number of diseases, and this one sounds like a fungal problem. It may also be due to inadequate growing conditions (i.e. nutrient deficiency, pH imbalance). If you suspect a nutrient problem, have your soil tested. Also, ifyou've been growing them in the same place year after year, it's time to move them to a new spot. If you don't "rotate" crops, diseases & pests of that crop can build up in the soil. Before planting, enrich the soil with compost or other organic matter, and once the cukes are growing vigorously, mulch well with newspaper covered with straw to maintain soil moisture. Spray the vines 2 or 3 times during the growing season with liquid seaweed fertilizer, which provides micronutrients to strengthen plants against disease and insect attack, and promotes fruiting. If you have trouble with cucumber beetles, I suggest my mother's never-fail solution: she places a couple of drops of oil infused with cloves, and places one near the base of each plant, and the beetles stay away. Hope this info is helpful!
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