Scientific research over five decades demonstrates the benefits of using SOP for high-value fruits and vegetables. Here are some examples of what researchers have found for specific crops.

Click on any crop below to read more about studies involving sulfate of potash (SOP).

Berries: SOP as the recommended potassium source due to problems of salt and Cl toxicity

Citrus: Sensitivity to chloride accumulations in the soil

Grapes: SOP as the preferred potassium source due to potential chloride injury

Onions and Garlic: SOP improves the yield and quality of onions by accelerating growth and improving ripening without bolting

Potatoes: SOP as a source of potassium for high yield potatoes can help to reduce the risk of salt injury and maintain high specific gravity in the tuber

Spinach and Lettuce: SOP addition provides higher dry matter yields

Sweet Potatoes: SOP positively affects sweet potato yields 

Tomatoes: SOP and tomato response includes higher yields, yields with better quality fruit, better uniform fruit, and increased shipping and storage tolerance