You’ll often read the recommendation to check soil pH, but what does that really mean? pH is simply a measure of how acid or alkaline a substance is, and soil acidity or alkalinity (soil pH) is important because it influences how easily plants can take up nutrients from the soil. Many gardening books and catalogs list the preferred pH for specific plants. The good news for gardeners is that, with a few exceptions, most plants will tolerate a fairly wide range of soil pH.
If your soil is too alkaline, add a source of acidity. The most common material to add is powdered elemental sulfur. As a rule of thumb, add 1 pound of sulfur per 100 square feet to lower pH 1 point. But as with lime, the correct amount will depend on your soil type and its initial pH. Testing your soil and following lab recommendations is the best approach if you want to lower the pH of an entire bed or area of your yard.