|I live in Colorado and this year I am going to attempt Blueberries. My soil pH is 6.8. In the directions that came with the blueberries, it recommended to only correct the soil pH by 0.5 units/year. Why can't I correct the soil to the correct pH before planting? Also what is best to correct the soil pH? The instructions suggest iron sulfate and others have suggested Mir-acid.
|Elemental sulfur is best. The effect is delayed because soil-dwelling bacteria need time to break down the added sulfur and lower the pH. The bacteria oxidize the sulfur; it then combines with water to form sulfuric acid, which acidifies the soil. Because this process relies upon active soil bacteria, sulfur is best applied in spring or summer, when the bacteria are most active. But you shouldn't have to delay planting -- mix lots of acidic peat moss in with the soil in the planting bed.
Learn more about blueberry culture by reading this article:
Hope this helps!