It’s important to have your soil tested to determine if you have a light and sandy soil, moderate and productive soil, or a heavy clay soil.
Get a soil test before you start adding fertilizers and amendments to your garden soil. This follows the old advice, “If it ain’t broke, don’t fix it.” Sometimes unnecessary tampering with nutrients or soil acidity can actually create more problems than benefits. (If you are starting with a raised bed, container or vertical garden and using pre bagged potting soil you can skip this step) Soil tests tell you the nutrient levels in your soil, basically a plant version of the nutrient guides on packaged foods.
They also note pH and organic content, two factors important to overall smooth sailing from the ground up. To have your soil professionally tested, call your local Cooperative Extension Service.
They are often listed under state or county government in the phone book. They can instruct you in how to obtain a soil-testing kit. You will need to follow the directions precisely for accurate results. When you receive your results the extensive chart can be a bit intimidating at first glance, however if you look for the below items it can help you begin to understand your soil composition:
• If the percentage of organic matter is under 5 percent, the garden will need extra compost.
• Nutrients will be listed separately, usually in parts per million (ppm). Sometimes they are also rated as available in high, medium, or low levels. If an element shows up as low, you should add a fertilizer that replaces what’s lacking.
• Soil pH refers to the acidity of the soil. Soil that is below 7 is acidic. Soils from 6 to 7 are slightly acidic; this is considered most fertile pH range or the Goldilocks zone (just right).
Soil results above a pH measurement of 7 is alkaline or basic soil, which can become problematic above a pH level of 8. Excessively acidic and alkaline soils can be treated to make them more moderate and productive. Add only the nutrients that your results show as being necessary and remember: More is not always better. Don’t feel compelled to add a little bit more of a fertilizer just because it promises great results. Too much of any one nutrient can actually produce toxic results, such as disease or worse. Apply only what is needed, and save your money for a better use, like more plants.