Why and How to Soil Test - The First Step to Better Soil Health
Updated: Sep 10
The first step to better soil health should always begin with a soil test. Every property is different. A good soil health regime should be tailored to your farm’s specific conditions and needs. Hence, why you test your soil!
Soil tests are not expensive, ranging anywhere from $30 to $80 a test depending on what you test for, but it gives you a baseline showing where you started and charts your soil improvements over time. A soil test can reveal critical issues with your soil that you would otherwise take a best guess at.
What Does a Soil Test, Test?
The basic “macro” soil test will tell you the fundamental composition of your soil and give you a good idea of the available nutrients for plants.
It will include basics like your soil PH — how acid or alkaline your soil is. It will tell you what your available nutrient levels are, testing nitrogen, potassium, phosphorous, magnesium, calcium and sulfur. Most soil tests will include your percentage of organic matter, the organic content readily available in your soil that provides nutrients to plants as it breaks down.
Depending on what crops you are growing or if the basic soil test indicates any imbalances, you might want to test your micronutrients. That’s called a “micro” soil test and usually checks for boron, copper, iron, manganese and zinc levels.
Most labs will offer recommended amendments for specific crops based on your soil test and have somebody on staff to answer questions and help you interpret your soil test. Otherwise, there are many resources online to help analyze your soil tests, including this great one from PennState Extension.
Test Your Soil Consistently
Once you get your first soil test done, stay consistent.
Use the same lab. Different labs will present things differently, even use slightly different metrics for measurement, which can make comparing your soil tests from year after year confusing.
Also, test your soil at the same time every year. Many nutrients (especially nitrogen) will test differently depending on how warm the ground is. If you test your soil in the early spring one year (when nitrogen is bound up by cold weather) but then the following year you test in mid-summer (when nitrogen is more plant-available because the ground is warmer), it could lead you to false assumptions about your total nitrogen availability and how your soil health regime has been influencing it.
How Often Should You Test Your Soil?
How often you test your soil will depend on what crops you are growing and, potentially, how closely you want to stay on top of changes in your soil.
If you are starting with a new soil improvement strategy, you might want to test every year for the first few years to chart the results of your efforts. Otherwise, it depends on what you are far