Soil testing can boost garden yield and quality, and improve your lawn and landscape

If you have not had your soil tested, now is a great time to do that. Each year, many homeowners fertilize their lawn, garden and landscape without a soil test. How do you know you are applying the right fertilizer at the correct amount? You might waste quite a bit of money on unneccessary fertilizer or wrong fertilizer. Worse yet, the excessive fertilizer might end up in our drinking water.

The soil test is an excellent measure of soil fertility. It is a very inexpensive way of maintaining good plant health and maximum plant productivity. The standard soil test provides the status of phosphorous (P), potassium (K), calcium (Ca), magnesium (Mg), pH, cation exchange capacity, lime requirement index and base saturation. Additional tests are also available for iron (Fe), zinc (Zn), manganese (Mn), soluble salts and nitrates.

How Do I Take Soil Samples?

1. Remove the top debris, residue, or turf thatch from the soil surface before taking the sample

2. Sample gardens, trees, shrubs, flower beds, and orchards 6–8 inches deep.

3. For the lawn, lift the sod and sample 3 - 4 inches deep.

4. Take soil cores or slices from as many places as possible to cover the entire sampling area by going zigzag - mix together and get enough to measure a little over a cup for the sample to bring in to the office.

5. Sample a row crop field or garden between rows to avoid fertilizer bands.

6. Sample when soils are suitable for spading or plowing.

7. Take separate samples from fields that have received different fertility programs.

How Much Does a Soil Test Cost?

OSU Extension in Delaware County offers soil tests at $25 per sample. You will need to bring the soil sample(s) to our office at 1610 State Route 521 Delaware, Ohio 43015. Please read the instructions below on how to take and prepare your soil sample for testing. Call us at 740-833-2030 for office hours and directions.

What Do I Get With My Soil Test?

You will receive a detailed soil test report and recommendations from a certified Master Gardener along with appropriate fact sheets.

How Long Does It Take?

It normally takes approx. two weeks to get a report and information to you (during busy season possibly 3 weeks estimated time).

When Do I Soil Test?

Soil samples can be taken in the spring or fall for established sites. For new sites, soil samples can be taken any time when the soil is workable. Most people conduct their soil tests in the spring. However, fall is a preferred time to take soil tests if one wants to avoid the spring rush and suspects a soil pH problem. Fall soil testing will allow you ample time to apply lime to raise the soil pH. Sulfur should be applied in the spring if the soil pH needs to be lowered.

How Frequently Should I Soil Test?

A soil test every two to three years is usually adequate. Sample more frequently if you desire a closer monitoring of the fertility levels, or if you grow plants that are known to be heavy feeders.

What Soil Sampling Tools Do I Need?

A soil sample is best taken with a soil probe or an auger. Soils should be collected in a clean plastic pail or box. These tools help ensure an equal amount of soil to a definite depth at the sampling site. However, a spade, knife or trowel can also be used to take thin slices or sections of soil.

The test results are only as good as the sample taken. It is extremely important to provide a representative sample to the testing lab so that a reliable test and recommendations can be made for the entire area. This can be accomplished by submitting a composite sample. A good representative composite sample should contain 10 - 15 cores or slices. Each core or slice should be taken at the same depth and volume at each site. Sample at random in a zigzag pattern over the area and mix the sample together in a clean plastic bucket.

Most samples need to be taken if the area was recently limed or fertilized. Separate samples need to be taken from lawns, gardens, flower beds or shrub borders. Separate samples should be taken from areas with distinctive soil types or plant performances