Adjusting Houston Soil pH


Posted by Sparki | Posted in Raised Garden Beds | Posted on 26-02-2012

If your plants exhibit yellowing of the leaves or slow growth, and you are not under or over watering, your soil pH may be a bit low or high.

Solving most garden “problems” is a process of assessing the possibilities and eliminating them one by one until you figure out what to do. You don’t have to be a scholar to be a great gardener; just a good detective.

Before you start adjusting your Houston soil pH levels, you should understand what it is you are doing. Soil tests will tell you if your soil is acid, neutral, or alkaline based on a pH scale from 0 to 14.

7 is considered neutral. The lower the number, the more acidic your soil is. The higher the number, the more alkaline your soil is. Does it really matter?

At some point in time, Agronomists discovered that low pH soils produced poorly. This gave birth to the practice of adding lime to soils to bring them to 7; into the neutral zone.

The Benefits of Soil Acidity

But the truth is, nature puts acidity into the soil from plant roots so that the actions of these acids can liberate minerals locked up in rock particles found in the subsurface clay layers.

When you add agricultural lime to “sweeten” soil pH, or raise it, you are providing a calcium rock compound that reacts with the acid clay in your soil system. The acid in the clay works on the lime to break down the calcium and release carbonic acid while the calcium is absorbed by the clay. Absorbed by the clay, the calcium then becomes available for plant use and adjusts the pH in the colloidal domain where plant roots absorb nutrients.

What happens to the carbonic acid? It decomposes into water and carbon dioxide. Carbon dioxide escapes from the soil taking acidity with it and the pH factor of your soil changes.

The benefit of all of this has to do with trading calcium off for hydrogen; pH tests really measure active hydrogen concentrations in the soil. Hydrogen has no nutritional value to plants.

So adjusting the pH level in your soil has more to do with loading depleted nutrients back into your soil system rather than removing acidity. Acidity is not a bad thing. In fact, it would be a very bad thing to remove all of the acidity in your soil. Without soil acidity, your plants will suffer nutritionally; and so will you when you eat them.

If you are going to go to the trouble of adjusting soil acidity for one nutrient (Calcium), you should consider adjusting for shortages or imbalances of Magnesium, Sodium and Potassium as well. That means having a lab run a complex soil analysis test.

Click here for more information on soil analysis testing.

Next: Raising Soil pH in Your Houston Garden


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