Answer: If you are growing the same varieties in the same location, but noticing a difference in flavor, there are several possible reasons. Overwatering could conceivably dilute the flavor a bit, however, I would consider excessive nitrogen levels to be a more probable cause.
Lack of sunlight, including more shady days prior to harvest is another possibility. Sunlight is required for the plants to produce carbohydrates including sugars, and therefore an important factor is flavor.
Another possibility is maturity at harvest. A few days can make considerable difference in the quality of a tomato. Picking too early or too late results in less than idea fruit flavor, texture and appearance.
Finally, it is difficult to give an accurate comparison from one year too the next. Many things can affect our sense of taste and perceived flavor. Also, time tends to change things. Remember the Barbara Streisand song..."could it be that is was all so simple then, or has time rewritten every line?"
Hope this helps. Thanks for the question!
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