Tomato Yellow Shoulders Due to High Temperatures and Nutrient Imbalance

This is the most common cause, confirmed by identifying sustained ambient temperatures above 85-90°F (30°C) and conducting a soil test. A soil test will reveal a pH level above 6.7, which inhibits potassium uptake, or an imbalance where Magnesium levels are high relative to Calcium and Potassium. These factors prevent the accumulation of lycopene in the fruit tissue.

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