Strengthen Your Soil with Agricultural Limestone

how to use limestone in the garden

You might take calcium supplements to strengthen your bones, but have you thought about giving a calcium supplement to your soil?

The calcium in agricultural limestone makes the cells of your plants healthier by strengthening their walls. This improves their stems and leaves as well as their root systems. It also helps them absorb and utilize sunlight more effectively.

One great use of limestone is to break up hard-packed clay soil. Many farmers and gardeners do this to improve their soil’s drainage and aeration.

But the most popular use of limestone is to make soil sweeterthat is, less acidic.

What Tums Do for Your Stomach, Limestone Can Do for Your Soil

Though some plants are acid loving, soil that is too acidic usually spells problems because the high acid levels cause nutrients to become locked up and unavailable. At the same time, fertilizer added to acid soil is not well absorbed and valuable minerals like nitrogen end up washing away. What’s more, too much acid kills beneficial bacteria that would otherwise work on the soil to enrich it.

Agricultural limestone is a time-honored solution used by generations of farmers and gardeners. Completely nontoxic, the calcium carbonate in limestone happens to be the active ingredient in Tums. So just as you might take an antacid made of calcium carbonate to neutralize stomach acid, when you add calcium carbonate in the form of limestone to your garden, it reduces the acid levels.

As the Tums commercial says, Concentrated relief that goes to work in seconds.

Soil Testing to Determine Soil AcidityAgricultural_Limestone

Just as you take Tums only when you have an acid stomach, you don’t want to apply limestone if your soil doesn’t need it. That’s why it’s best to test your soil.

These days soil testing is quick, easy, and inexpensive. You can get an inexpensive mini-tester that you stick in the ground whenever you need a reading. Within seconds it will tell you your soil’s pH.

If you want an extensive soil test that will also tell you the levels of the various minerals in your soil, get in touch with the nearest Extension service, or contact a professional gardening or landscaping company.

What is pH?

The pH of your soil indicates how acidic or alkaline it is. Acidic soil has a pH lower than 5 while alkaline soil has a pH greater than 7. The ideal pH for most plants is somewhere in the middle.

Master gardeners fine-tune the pH of their soil depending on what they’re planning to grow. To do this, consult a chart that shows the optimal pH for various plants.

Limestone to Break Up Clay Soil

An important but lesser known use of limestone is to break up hard-packed clay soil. This improves its drainage and aeration. All you have to do is apply the limestone to the surface of the soil and it will work its way in and break it up through a chemical reaction called flocculation.

healthy_soilWhat happens is that the calcium in the limestone interacts with the silicon in the clay and causes it to separate on a molecular level. This causes the clay to become less dense without any need for elbow grease.

Limestone: Inexpensive and Effective

If a professional soil test indicates you have a severe deficiency of magnesium as well as a need for calcium, go with dolomite limestone which is calcium and magnesium. Otherwise, we recommend plain old limestone, because it does the job and does it well.

Happy Gardening from all of us at GrowJoy.

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