Many of soils throughout Connecticut tend to be more acidic, formed as rocks were ground and deposited by glaciation. The pH of soils cultivated for vegetable growing typically declines (becomes more acidic) gradually from the removal of calcium, magnesium and potassium ions–by leaching and crop uptake–and from the use of acid-forming fertilizers. Testing every year gives a more complete evaluation and is also appropriate when significant changes have been made in the fertilizer program. Reviewing fertilizer labelling is essential.