Soil Testing | SoilNOW

Asking a few key questions can guide us in managing our soils more effectively:

What soil characteristics or challenges are present?
How do these characteristics or challenges impact the soil?
What management options are available?
How we can implement these practices?

Field observations can provide some of this information — this can be as simple as looking at the soil in your garden or farm, and noticing any changes or challenges with the soil itself or plants growing in the soil. Sometimes it’s also helpful to take a soil sample for laboratory testing, which can provide excellent information to inform management plans and trouble-shoot any challenges.

Remember: Before submitting a sample, always check with the lab for the latest submission guidelines, available packages, and other information!

Also note: urban soils, especially those high in organic matter, have some additional considerations. This resource on “Management Practices for High Organic Matter Soils: Urban Farm Soil Test Interpretation” from CCE Harvest NY and CCE Cornell Vegetable Program may be helpful.

Collecting & Submitting a Soil Sample

A good soil sample will represent the soil environment, including any variation across the site and the depth being managed. Levels of soil properties like pH, nutrients, and contaminants can be different in different places. To take a representative soil sample, it can help to think of your site as made up of units of different use/management areas or soil characteristics. You can then sample these units separately to better characterize the different areas of your site.

Links for more information:

How to Take a Soil Sample (step-by-step instructions from CCE Tompkins County)

Soil Testing information from the Healthy Soils, Healthy Communities Program (information, resources, and fact sheets)

How to Submit a Soil for Nutrient Analysis (video from Cornell Soil Science course)

How to Take a Cornell Assessment for Soil Health Soil Sample (video from Cornell Soil Health Lab)

Soil Sampling for Field Crops (agronomy fact sheet from Cornell University Cooperative Extension)

Before collecting and mailing your soil sample, be sure to check with the laboratory you choose for any special requirements. Labs often specify the amount of sample needed, the preferred moisture content, and packaging instructions. Labs may also request additional information about the soil, the site use (including plants grown), the sampling date, or other factors that might guide the interpretation of results.

pH Testing

pH measures a soil’s acidity, which affects the availability of soil nutrients to plants. For most horticultural crops the ideal pH for nutrient availability is around 6.2‐7.0 (see Optimum pH Ranges for Garden Crops). Generally, a high pH can result in deficiencies of phosphorus, iron, manganese, copper, or boron. A low pH can result in deficiencies of calcium, magnesium, phosphorus, potassium, or molybdenum. Very low pH can result in plant aluminum toxicity. pH levels can also affect the amount of toxins that can be taken up by plants or move through the soil.

Visit our pH page for more information and management resources.

Test Submission

There are numerous laboratories in NYS that can determine soil pH as well as other soil properties. Some options include the Cornell Soil Health Laboratory, Dairy (Agro) One, and the Urban Soils Lab at Brooklyn College. Cornell Cooperative Extension and other organizations sometimes also have workshops or events that will provide free analysis – you simply have to bring a sample.

Testing at Home

There are a wide variety of store-bought products that can easily determine your soil’s pH, but some can be expensive. These options include pH paper, liquid or powder reagents, as well as electronic meters or pens. If available, a pH meter can quickly and efficiently measure multiple samples. You can find more information on our page Using and Maintaining pH Meters with Your Soil.

There are also do-it-yourself soil pH tests that can be made and used at home. These include vinegar and baking soda as well as a homemade red cabbage juice method. For more details, see How to Test Soil pH.

Additional Resources:

How to use Cornell’s soil pH test kits (demo from Cornell Soil Science course) NOTE: these kits are no longer being produced by Cornell.

How to Measure Your Soil pH (pH meter demo and other info/tips from Alberta Urban Garden)

Find Out if Your Soil is Acidic or Alkaline Using Vinegar and Baking Soda (demo from GroMór)

Red Cabbage pH Indicator (demo from The Sci Guys: Science at Home)

Red Cabbage Color Indicator Chart (pH color chart from Stanford University)

Soil Test Kit (Powder) for pH & NPK (demo from Name It Build It)

Nutrient Testing

A soil test can provide information about the nutrient levels in your soil and what you may need to add (as fertilizer) for successful crop growth. Plants need nitrogen, phosphorous and potassium (macronutrients) as will as micronutrients to grow. Deficiency or excess of these elements will impact the health and productivity of plants. In addition, the pH (acid/alkaline level) of your soil impacts how much of the soil’s nutrients your plants will be able to use.

Test Submission

The Cornell Soil Health Laboratory offers several soil health analysis packages. The properties measured vary with each package, but include testing for nutrients in addition to parameters like pH, organic matter, wet aggregate stability, carbon, nitrogen, hardness, and more.

The Dairy One Soil Laboratory provides fertility analysis and recommendations in a variety of packages suitable for gardeners and many others. The “Standard” package (803) is often best for home gardeners. This video on Submitting a Soil Nutrient Analysis (from our Cornell Soil Science course) can help guide you through the process. See also this list of crop codes Dairy One use for submission.

The Urban Soils Lab at Brooklyn College offers nutrient testing as well as lead screenings and tests for other soil properties (pH, salt content, organic matter content, texture).

Check with the labs for updated details on submission instructions, pricing, and other information.

Test Results

If you choose the testing package described above, results will be returned to you in a printed and/or a email form and will include an analysis of nutrients, pH, and organic matter in your soil. Note that the test does not analyze nitrogen; this nutrient is present in many forms in the environment (not all of which are available to plants) and the forms can change on an almost daily basis. Here is a sample results report.

If you have included a plant name on the submission form, the results will also provide Soil Fertilizer Recommendations for amounts and ways to apply fertilizer and pH amendments to your soil. For more information on how to interpret your results, including what information the results provide and planting recommendations, see this video on Soil Nutrient Test Results from our Cornell Soil Science course.

For additional resources on how to manage your soil nutrients, visit our Fertility and Fertilizers page.

Note that home test kits for nutrients such as nitrogen, phosphorus, and potassium are also available commercially, but are not as reliable as lab tests.

Soil Health Testing

While there are no “good” or “bad” soils, the qualities of any individual soil may be more or less suitable for a desired use. Soil health goes beyond pH and nutrient testing to provide insights into the full range of a soil’s function, as well as information to guide management decisions. Soil health testing identifies physical, biological and chemical constraints so growers can improve and maintain sustainable, healthy, and productive soil and crop management practices.

New York Soil Health provides extensive resources to growers, including soil health guidelines and best management practices.

Test Submission:

The Cornell Soil Health Laboratory offers packages and add-on services for measuring soil health by testing for nutrients, pH, organic matter, and other properties. There are a number of tests available so be sure to contact the lab with questions, and for the latest information on pricing and sample submission.

Understanding Results:

The soil health test evaluates a suite of individual soil characteristics, which when combined provide a comprehensive overview of the health of the soil. These results provide insights into effective practices to improve the quality and performance of the soil, and to guide an overall management plan.

To see a sample of the report summary, visit the Cornell Soil Health Laboratory’s Interpreting Results page. Additionally, the Comprehensive Assessment of Soil Health manual includes more information on soil health assessment options (available for free download).

Contaminant Testing

Soils sometimes contain contaminants that can be harmful to people or plants. Testing levels of lead and other metals can help you learn more about your soil, and answer questions to inform your next steps. Our partner program Healthy Soils, Healthy Communities provides additional information. Sometimes it makes sense to skip the testing step and focus on Healthy Gardening Practices instead. These FAQs can help you decide if testing your soils is likely to be helpful.

If you decide to test your soil, be sure to check with the lab you choose about any special requirements for collecting and submitting soil samples. Here are a few suggested resources to help you find a lab to test for lead or other heavy metals:

New for 2024 – New York State Community Gardens Soil Testing Program: The NYS Department of Agriculture and Markets invites eligible organizations to apply for community garden soil testing.
The Urban Soils Lab at Brooklyn College offers lead screenings and tests for other soil properties (pH, salt content, organic matter content, nutrients, texture).
The NY State Department of Health Environmental Laboratory Approval Program provides a searchable database of certified labs. Using a certified lab is important when testing has implications for public health or may be used in legal proceedings. Commercial labs may also offer additional tests or services not available through college or university labs or soil screening events.
University labs in other states offer a variety of testing packages as well.
Please note that Cornell is not currently offering heavy metal testing services.

Understanding test results can be confusing, and there is no clear line as to what is considered “safe”. Sometimes, results show that contaminant levels are higher than health-based guidelines or levels recommended by other sources. Generally in these situations it is wise to take steps to minimize people’s contact with contaminants — both children and adults. The Healthy Soils, Healthy Communities guide to Metals in Urban Garden Soils outlines acceptable levels for key contaminants of concern for human and plant health, answers common questions about how these metals behave in garden soils, and recommends action steps for healthy gardening.