Understanding your soil test results can be difficult. In a new, easy-to-follow video, Extension horticulture educator Christy Marsden shows you how to interpret the U of M Soil Lab's standard soil test results report from top to bottom. She walks you through each section of the report, and weighs in on how to make the right decisions for your garden based on the results.
Key takeaways from the video
- The three nutrients your plants need the most of are nitrogen (N), phosphorus (P), and potassium (K). Bags of fertilizer often display N-P-K values as a ratio (for example, 10-10-10). Your soil test report provides a N-P-K ratio recommendation for your soil. Do your best to buy a bag of fertilizer that has a ratio as close as possible to what the report recommends, without going over on phosphorus.
- The reason you don't want to go over on phosphorus is because applying too much phosphorus fertilizer can be harmful to the environment. Compost can also have phosphorus, so make sure you're not applying too much compost either. (For more information, check out this recent article: How much compost should you apply to your garden?)
- Nitrogen-deficiency is a common problem in vegetable gardening, so make sure you apply enough nitrogen to meet your crops' needs.
- If your soil pH is too acidic or alkaline, it can inhibit your plants' ability to take up nutrients. You can correct your pH to bring it back into an optimal range. (Learn more in this blog post: Does your soil have a high pH? Fall is the best time to amend it.)
- Knowing whether your soil is coarse-, medium-, or fine-textured can help you decide which plants/crops are best suited for your soil.
Soil testing resources
- U of M Soil Testing Lab
- Ask a Master Gardener
- Video: Why test your soil?
- Video: How to Take a Soil Sample From your Lawn or Garden
- Managing soil and nutrients in yards and gardens
- Fertilizer calculator
University of Minnesota Extension’s urban nutrient management communications is supported in part by Minnesota’s fertilizer tonnage fee through AFREC, the Agricultural Fertilizer Research and Education Council. Learn more at MNsoilfertility.com.