Understanding Soil Ph

Understanding Soil Ph

The pH of soil refers to the measured level of acidity or alkalinity in your soil.

The pH scale ranges from 1.0 up to 14.0 with 7.0 being neutral.

If soil pH is higher than 7.0 it is alkaline.

If the soil is lower than 7.0 it is acidic.

It is important to know your soil PH because it can have a great effect on which nutrients are available to your plants. When the pH is too high or too low, your plants may get too much of some nutrients and not enough of others.

Testing Soil pH

Checking your soil pH is fairly easy. 

It only takes a minute to get your pH reading and the testers can be used over and over.

It is very important to take samples from different sites in your gardens and beds. pH can vary even within a small area.

Adjusting Soil pH

If your pH test shows your soil to be between 6.0 and 7.0 you do not need to adjust the pH, it is perfectly fine for most plants.

For pH below 6.0 (acidic soil)

For low pH readings you need to add lime to your soil. Garden lime (calcium carbonate) is readily available at garden centers hardware stores and home-and-garden stores.

Applying about 5 to 10 pounds of garden lime for every 100 square feet of garden area will raise the soil pH by one full number (from 5.0 to 6.0, for instance).

Add the right amount based on your initial soil pH reading and work it into the top few inches of soil.

You can apply the lime at any time of the year but it’s best to add several month before planting.

Thereafter you should test pH yearly and adjust as necessary.

For pH above 7.0 (alkaline soil)

To lower pH you have your choice of soil additives – ground sulfur, calcium sulfate, iron sulfate, aluminum sulfate, or garden gypsum. These are all readily available at garden centers hardware stores and home-and-garden stores.

Apply them according to the package instructions (each will be different), depending on how much you need to lower your soil pH.

Thereafter you should test pH yearly and adjust as necessary.

May 21, 2021
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