Soil Testing

Our Soils Testing Lab is operated by Master Gardener™ volunteers in collaboration with MG Program Coordinator, Small Farms Agent, and Soil Scientist Logan Bennett.

Our soil testing results give the pH, Nitrogen, Phosphorus, and Potassium levels. These are the key tests for the home gardener. Along with the results you will receive links to several great OSU publications. The cost per soil test is $15 for the public.

So dig up a sample and drop it by the Extension Office (1134 SE Douglas in Roseburg) and we’ll test it for you! Payment due at drop-off (cash or check).

How To Take A Soil Sample

Soil testing can be done whenever your soil isn’t frozen or overly wet. The best time of year for sampling is in spring or fall. Sampling new lawn or garden areas several months in advance allows time for making recommended adjustments before planting. Plan to provide soil samples for each location that you’ll be planting.

Established lawns, for example, need nutrition that is different from gardens or new lawns. So, area-specific samples will deliver area-specific results and recommendations.

Sample front yards and back yards separately; conditions will vary for each.

Get a shovel, plastic bucket, container, and garden trowel. Be sure each is clean of any contaminating chemicals or dirt.

  1. Pick a typical spot six by six inches, remove any plants, and scrape mulch and leaf litter from the soil surface. Dig a hole 6 to 8 inches (15.2 to 20.3 cm) deep, and set this shovelful aside.
  2. Use the trowel or shovel to scrape down one side of the hole, digging out a half-inch vertical section of soil to get a representative of the vertical part of the hole and the bottom and place it in the bucket.
  3. Collect several cores or slices by walking in a zig-zag pattern over the area. Consider 5-10 cores as the minimum for home gardens and lawns up to 10,000 square feet in size. At least 15 to 20 samples should represent larger areas.
  4. Mix cores thoroughly in a clean pail for a composite lab sample. Remove anything not soil, such as roots, worms, or rocks. The greater the number of collected cores mixed together, the better the sample will represent the average condition of the sampled area.
  5. Fill a plastic bag or container with 2 cups of the mixed soil. Soil must be quite dry for testing, so you may want to let it dry before bringing it in.

Soil Samples may be dropped off during regular business hours of 8 am to 5 pm at the OSU Extension Office located at 1134 SE Douglas Ave, Roseburg, OR 97470 (next door to the courthouse).

The charge for soil testing is $15 per sample, payable via cash or check when the sample is brought in.  Test NPK (nitrogen, phosphorus, potassium) and pH (acidity).

Results will be mailed/emailed to you within 2-3 weeks, depending on whether the sample comes to the lab dry or needs time to dry thoroughly before testing.

Feel free to contact us via email at if you have any questions.