Organomananswered grow question 10 months ago 6.5 - 7.0 in soil is perfectly fine. Adding acidic water (5.0) to soil will not change the pH of the soil. To lower the pH of the soil, top dressing with agricultural sulfur will lower soil pH...........but if your soil is anywhere between 6.2 and 7.2, I really wouldn't worry or try and change anything.