What Is the Soil PH Level?

Among the analyses you will get information on will be a factor called “pH”. Now, a lot is made of soil pH. In laymen’s terms, pH is a measure of the soil acidity or alkalinity. The scale goes from 1.0 to 14.0, with 7.0 being neutral. The lower the numbers go from 7.0, the more acidic the soil. The higher they go above 7.0, the more alkaline. The reason soil pH matters is that nutrients in the soil are only available to plants if the soil pH is within a certain range. Certain plants actually prefer one or the other, sometimes even drastically. Rhododendrons, for example love an acidic soil. Blueberries too. Yet, other plants like Lilacs and Clematis like just the opposite. Ironically, soils, no matter how much we augment them originally, will eventually revert to the original pH. It is always worth testing over time with an eye to that important fact.

Changing pH

If your pH is off, you will get a recommendation for adding either lime, to raise the alkalinity, or sulfur, to lower the pH. This is easy enough to do and should be done in stages, so as not to shock the plants. Generally it is recommended that you not add more than 5 pounds of lime or sulfur per 100 sq. ft. of existing garden. If you were wise enough to test your soil before putting in a garden or lawn, go ahead and dump in the whole recommended amount. This is another example of why some solid and thorough planting is a grand idea. Shoot for the median of 7. If you are slightly off that figure one way or the other it won’t make a lot of difference in any case. There is a large tolerable range that lets plants thrive.

Amending The Soil

After analysis, if you find you need to add nutrients to your soil, you’ll have the choice of organic or inorganic. Inorganic fertilizer has some pluses in its favor. It is usually cheaper than organic fertilizer and it acts more quickly. However, it does nothing for the soil and in some cases actually damages the soil with its higher salt content. So inorganic fertilizers don’t actually amend the soil, they simply feed the plant. It is kind of like a human being trying to survive on vitamin supplements and no substantial food. There have also been some recent studies that claim plants build up a resistance to inorganic fertilizers and require more and more of them to get the same results.

That organic fertilizers are slower acting is actually a good thing. They release their nutrients over a period of time. There are many good complete organic fertilizers on the market. A complete fertilizer is one that contains all three primary nutrients, nitrogen, phosphorus and potassium. (Learn how to read fertilizer labels. They typically contain 3 main elements: Nitrogen, Phosphorous and Potassium. These 3 are the literal building blocks of plant health.). You can also get supplemental nutrition from products like manure and fish emulsion for nitrogen, bone meal for phosphorus and wood ashes for potassium.