Allen County

extension news notice

Purdue Extension: Expert Resources for COVID-19

Soil Sampling

May 19, 2020
Soil sample supplies

Purdue Extension - Allen County offers soil testing services to analyze the nutrient levels of your soils. We also help you understand your results and find solutions. Soil testing fees are $20 per sample (cash or check). We are now offering contactless drop-off services at our office. 


Here is some helpful information to make sure you get most accurate results for your money.

Where and When to Sample

Keep samples from different areas separate. Areas treated different or with different characteristics will have different soil profiles. Examples of areas which should be treated different include

It is best to take samples in spring or fall before applying fertilizer. Give yourself enough time to get results back and determine which products to buy for your soil.


  1. Gather supplies
    • soil probe or spade
    • plastic bucket (metal buckets may transfer trace minerals to the soil)
    • trowel
    • bag(s) for soil
  2. Clear surface of debris
  3. Take at least 5 random samples from the area
    • generally moving around the area in M or Z shapes work well to cover the space
    • samples should be 3" deep for lawns, 6-8" deep for gardens/crops/shrubs, and 8-12" deep for trees
  4. Place soil in bucket
  5. Mix soil and fill bag (2 cups of soil per sample)

For an easy to directions watch THIS VIDEO from our friends in Illinois. 


Reference the new Purdue Extension publication HO-71-W "Collecting Soil Samples For Testing" for more detailed procedures

Ensure you have 2 cups of soil

Sample every 2-3 years at the same time of year

Allow time for samples to be processed before fertilizer needs to be applied. This can take up to 2 weeks but is often much shorter.


Contact James Wolff (Agriculture and Natural Resources Educator) or Terri Theisen (Horticulture & Urban Agriculture Educator) for more information.


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