Answer: The sweetness of fruits has a lot to do with their variety, with the weather, with their degree of ripeness, and with the amount of water they receive. Deep watering every 4-7 days during the summertime should be sufficient for your fruit trees. If your trees are producing lots of small fruits, you can do some thinning in the spring to reduce the numbers of fruits your tree will produce. This will result in fewer, but larger and sweeter fruits. For instance, if you remove half of the fruits in each cluster, you'll have better fruit. Next spring give it a try on your peach, plum and nectarine trees. I think you'll notice the difference. Sounds as though you are watering enough and you can't change the weather, so the best you can do is concentrate on thinning the fruits just as they begin forming in the spring.
Hope you have a wonderful harvest!
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