Answer: Since it sounds as if your plants were otherwise healthy, it could be a pollination problem. When the fruits are just emerging and then die, it could be that the female blossoms weren't pollinated. This sometimes happens early in the season, before the male blossoms appear. It can also happen during cool spells when pollinators are less active. Also, there aren't as many pollinators around as in past years. Bees are being devastated by a mite.
You can hand pollinate the blossoms yourself by taking a small artist?s paint brush or Q-tip and rubbing the pollen from the male (without a small fruit behind the flower) onto the female (with a small fruit behind the flower).
Also, plants need phosphorous to produce flowers and fruits. You might want to use a side dressing of fertilizer high in phosphorous (the middle number) or an organic source, such as bone meal. Scratch it into the soil to the side of the plant's roots and water well before and after applying.
To prevent possible fungal problems, perform cultural techniques like not overwatering, using a drip watering system rather than constant overhead sprinkling (wet plants create a perfect environment for disease), and growing vines on a trellis to improve air circulation or leaving space between plants. Mulching with a layer of dry organic material, such as straw, can also be useful. I hope this info helps. If you have problems again this year, please send another email detailing the condition of the plants as well.
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