Achieving the optimal pH can involve modifying the soil with elemental sulfur, especially in cases where the soil is too alkaline ...

Use Iron Sulfate To Lower Soil pH Levels Iron or ferrous sulfate (FeSO4) works similarly to aluminum sulfate, except it gives the soil a little iron, which is an essential plant nutrient.

Aluminum and sulfate work together to lower the soil pH, further facilitating the absorption of aluminum by the plant. By ...