How to Test Your Soil
Soil Health
A soil test is one of the most useful and inexpensive steps a home gardener can take before planting. It gives you a factual picture of what is happening below the surface so you can make informed decisions instead of guessing. For US gardeners, the most reliable results come from a laboratory soil test, and your local Cooperative Extension office can point you to a trusted lab in your state.
What it is
A standard laboratory soil test typically reports your soil pH, the level of major nutrients such as phosphorus and potassium, and often the percent organic matter. Soil pH describes whether your soil is acidic, neutral, or alkaline, and it strongly affects how well plants can take up nutrients. Many labs will also note your soil texture or cation exchange capacity, which relate to how the soil holds water and nutrients. The report is a snapshot in time, so soil chemistry can shift gradually from season to season and with changing management.
What to do
Start by deciding which area you want to test, such as a vegetable bed, lawn, or new garden plot, and test each area separately. Using a clean trowel or soil probe, collect small cores from 6 to 10 spots across the area, each roughly the depth of the root zone, then mix them in a clean plastic bucket to form one composite sample. Let the soil air dry, place the recommended amount in the lab bag, fill out the form describing what you plan to grow, and mail it to the lab. When your report returns, follow the interpretation and any recommended rates from your Cooperative Extension rather than applying products by guesswork.
Tips
Test in late summer or fall when labs are less busy, and retest every two to three years to track changes over time. Always label each sample clearly and keep separate beds separate, since averaging very different areas can hide real differences. For reading your results and deciding on any specific amendment rates, contact your local Cooperative Extension office, which can tailor guidance to your region, soil, and crop.
General guidance for US gardens. For specific nutrient, pH, and amendment rates, have your soil tested through your local Cooperative Extension office. Page updated Aug 4, 2026.