We all know that the predominate soil here in the Charlotte area is clay. While this clay is fantastic for pottery classes and detergent companies, it isn’t so great for the gardeners among us. This article is intended to answer the four big question about liming. Why, when, how, and how much to Lime. If you have any questions at any time please don’t hesitate to call us at 704.525.2682 or stop by Blackhawk and have one of our extremely knowledgeable Lawn and Garden associates assist you with any questions.

In addition to rock hard clay soil acidity is a pervasive problem in the Charlotte area. Acidic leaching from rainfall, irrigation, organic matter decay, and over fertilization leads to highly acidic soil. Lime is the key to solving both problems. Not only does it help loosen soil, it also lowers the acidity (raising the pH) by acting as a base. It also provides the critical plant life cycle nutrients calcium and magnesium. Generally speaking, if you fertilize regularly, you also need to be liming regularly. A dollar spent on lime is going to result in much better plant health and growth than another dollar spent on fertilization.

1.  WHY

We have all encountered that sun baked clay with a consistency is somewhere in the hardened brick family. This hardening is caused by the clay’s molecular make up which consists of extremely small particles that naturally tend to bind or stick together. Adding lime to the soil effectively breaks those molecular bonds, making the soil more suitable to gardening. Lowering soil acidity is important because it allows plants to absorb good nutrients and block toxic levels of other elements. When acidity (low pH level) is too high, important nutrients like nitrogen are not able to be absorbed by the plant. At the same time other elements like aluminum (naturally abundant in the earths curst) are so readily available that they become toxic to the plant. Lime lowers the soil acidity because it is a base. Bases naturally raise pH levels and neutralize acids. The clay here in Mecklenburg County is naturally low in calcium and magnesium. Lime provides a easy to use, economical source for both nutrients. These nutrients are important because without them a plant can not complete its life cycle.


2.  WHEN

When to lime? Anytime! Lime can be spread year round because it naturally lacks salt. Spreading lime in the winter is most advantageous because it will let you take advantage of the natural freezing and thawing cycles of the soil. This in combination with the lime will loosen the soil the fastest.


3.  HOW

Spread the two forms of dolomitic lime, powered and pelletized, using a simple broadcast spreader. Whether hand pushed or pulled behind a riding lawn mower, a broadcast spreader is the easiest and cleanest method to spread lime. You can also spread the lime by hand. This is extremely messy. We strongly recommend that you wear gloves, eye protection, and a dust mask while doing so.

Helpful Hint:

Pelletized lime is simply powdered lime formed into pellets. Pelletized lime is a little more expensive, but a lot less messy to apply.

Helpful Hint:

Always throughly wash and lubricate (with WD-40) the spreader after spreading lime. Lime is highly corrosive and will cause any metal parts to quickly rust. Washing will greatly increase the life of the spreader.

Helpful Hint:

When liming a garden, turn the lime into the soil, as you would in preparing a garden. This is the best way to ensure the plants are able to benefit from the full effects of the lime.



Determine the Acidity of your soil:

To determine the acidity, you have to test the soil. You can do this by purchasing a home soil pH kit. Or you can send a sample to the Extension Service (link) in Raleigh for a free test. If you send the sample off, expect to wait eight weeks for the results. As a general rule, the soil around the Charlotte area has a natural (un-limed) pH value between 4.5 to 6.0.

Determine how much lime to use:

Plants like azalea, rhododendron, pine and spruce grow best in soil with a pH level of 5.0 – 5.5. Most other plants grow best in a soil with a pH level of 6.0 to 6.8.

The rule of thumb for raising your pH level by 1 is 40lbs of lime per thousand square feet of yard. But never apply more than 50lbs of lime per one thousand square feet at a time. Instead wait one year, retest soil and reapply again.  This is a long-term project – it will take several years to get most soil to a balanced state.  Too much lime, too quickly can over-alkaline the soil, causing yellowing which is difficult to correct.  Soil testing to determine how much lime you’ll need is critical.

Retest to determine Acidity Level: We recommend testing the pH level of your soil annually. Once again you can do this by purchasing a home soil pH kit or sending a sample off to the Extension Service in Raleigh.


We hope this article has helped explain why, when, how and how much of liming to do here in the Charlotte area. Remember that a dollar spent on liming will produce much better results for plant health and growth than another dollar spent on fertilizing. If you have any questions or would like to talk to an expert about your unique yard problem, don’t hesitate to call us at 704.525.2682 or stop by Blackhawk and and have one of our extremely knowledgeable Lawn and Garden associates assist you with any questions.