Lots of people try to guess the pH of their soil based on appearance — it can’t be done! The only way to know for sure is to test the soil! How sweet is the soil around your home? If you don’t know, you need to find out. But don’t go out and taste a spoonful — have it tested by bringing a sample to the Cherokee County Extension office.
“Sweet” soil is simply soil that is alkaline, measuring higher than neutral on the pH scale. The pH is one of the most important things to know about your soil. It shows how acid or sweet your soil is. The lower the number, the more acidic the soil.
It’s important to know your soil’s pH because each plant has a certain pH level at which the nutrients in the soil are most available to it. If the pH of your soil is too low or too high, your garden and flower plants, lawns, shrubs and fruit trees could be starving for those nutrients, even if they're right there in the soil.
So what’s the best pH? It all depends on the type of plants that you are trying to grow. Take centipede grass, for example. The pH for good centipede growth is 5.5, although it will tolerate a pH below 5.0. Other grasses, like fescue, zoysia and bermudagrass need a higher pH, somewhere around 6.2. Vegetable gardens and most flowers and shrubs grow best at a pH of 6.0 to 6.5. Acid-loving plants, like azaleas and blueberries, however, grow best at a lower soil pH, less than 5.5.
If you find you have a low pH, add dolomitic or agricultural lime. Dolomitic limestone contains both calcium and magnesium which corrects the soil pH and helps plants produce healthy, vigorous growth. Fortunately, that may be the cheapest thing you soil needs.
So, whatever plants you have, whether they’re fruit trees, shrubs, vegetables, forages or turf, you will not know if you need to add lime to your soil, or how much lime to add, if you don't know your soil's pH. I recommend testing your soil at least every three years if you are a homeowner, more often if you are producing a commercial crop.
Take a soil sample that is representative of the area. To do that for a lawn, get samples from 10 to 20 spots from a 4 inch depth. For all other plants, take the samples from a depth of 8-12 inches. Then after thoroughly mixing the 10 to 20 samples together, place 2 cups of soil in a plastic sandwich bag. When you bring that to our office, we’ll help you transfer the soil for testing into one of our special soil test bags.
Bring your soil samples to Cherokee County Extension office and we will mail your samples to the University of Georgia’s Soil Testing Lab in Athens. We should have your test results back in about 10 days and you can have them mailed or emailed to you, complete with recommendations to fertilize and adjust that all-important pH.
As your county agent, I will be able to see your results on my compute as well, so if you have any questions or concerns, you can call me and we’ll look at your test results together. The fee for this service is only $8 per sample. I guarantee it’ll be the best $8 you ever spend on your yard!
Information about Extension Solutions for Homes and Gardens can be found on the University of Georgia Cooperative Extension website, www.ugaextension.com/cherokee , "Learning for Life". Or contact the Cherokee County Extension Office, 100 North St., Suite G21, Canton, GA, 770-479-0418.