Soil Sampling Procedures

Soil Sampling Procedures

To be a reliable guide for addition of fertilizer, the sample must represent the soil condition of the area sampled. Laboratory results can only tell you what is in the sample you send. It is the sample takers job to take a truly representative and unbiased sample of the area.


  1. Soils that vary in type, crop growth or past treatment should be sampled separately providing they can be fertilized separately.
  2. An auger, soil sampling probe, or spade can be used.
  3. Scrape away surface litter. If using an auger or probe, obtain a sample about 10-12 inches deep. If using a spade, dig a V-shaped hole about 10-12 inches deep, then cut a thin slice of soil from one side of the hole. Save the center portion of this slice.
  • Avoid unusual areas, such as places where fertilizer has been spilled, gated areas where livestock have congregated, or poorly drained areas. It is advisable to stay at least 50 feet away from barns, roads, and fence rows.


Because of soil variation, each sample should contain a small portion of soil from approximately 15 locations. Mix them together in a clean plastic bucket and place about 1 pound or 3 cups in the soil sample bag.

  • Sample should be clearly marked with your name, address, and sample identification.
  • If recommendations are needed, fill out a request sheet and/or the front of the soil sample bag. The information is needed to make accurate recommendations. Be sure the sample on the request sheet corresponds with the number on the sample bag.

*If samples are shipped to our physical address, use zip code 83301. If samples are shipped to our Post Office Box, use zip code 83303.

2924 Addison Ave E Twin Falls, ID 83301
208-734-3050 * 208-734-3919 (fax)