Soil sampling
Why should I do a soil test?
Soil tests help to identify production problems related to nutrient deficiencies or imbalances. If you have problems with poor or irregular plant growth, hard to manage weeds, low crop yields or poor quality forages, soil testing can help.
Benefits of Soil Testing:
- Determines nutrient levels in the soil
- Determines pH levels
- Helps the decision making process of what nutrients to apply and how much
- Potential for higher yielding crops
- Potential for higher quality crops
- More efficient fertilizer use
Source: NRCS Soil Testing Handout
Soil Sampling Protocol
Collecting your own soil sample is a simple process. If you do not have a soil probe, all you need is a clean spade and a clean plastic bucket or plastic bag. You can follow the CDFA Soil Sampling Protocol or the NRCS guide on how to collect your own soil sample.
Once you have your soil sample in a bag (most labs want about 2 lbs of soil, which fills about half of a gallon-size zip plastic bag) , make sure to label it with your name, email, date, exact location of your field, and any other useful information. You can drop off your sample to a laboratory during their business hours, and usually get results within a week.
List of Soil Testing Labs in Kern, Tulare, Kings and Fresno
The listing provided is for informational purposes only and do not constitute endorsement or recommendation by University of California Cooperative Extension, nor is criticism implied of similar companies that are not included.
If you would like any laboratory information added or edited, please email mridoutt@ucanr.edu
| Laboratory Name | Address | Phone / Fax | Cost of soil organic matter analysis | Notes |
| Valley Tech Ag Lab | 2120 South K St Tulare, CA 93274 |
559-688-5684 |
$20 for organic matter analysis // $50 for full soil analysis |
|
| Fruit Growers Laboratory Inc | 9415 W. Goshen Avenue Visalia, CA 93291 |
559-734-9473
|
$50 for 1st time sampling // $23 after 2nd sampling |
Company provides sampling bags. |
| Dellavalle Laboratory, Inc. | Laboratory: 1910 W. McKinley Ave Ste 110 Fresno, CA 93728 Peninsula Messenger Service: 2015 Westwind Dr., Suite 10, Bakersfield, CA 93301 Dellavalle Consulting office 1216 N Douty Street Hanford, CA 93230 |
800-228-9896 |
$28 for organic matter analysis // $99 for soil fertility package |
On the sampling bag include a label with the description of sample. Drop off locations available in Bakersfield and Hanford. |
| JMLord, Inc. |
4184 N. Knoll Dr. |
559-268-9755
|
$11 for organic matter analysis // $63 for complete soil package + organic matter |
Samples can be mailed to the laboratory with a check. Applicant must include a label with their name, address, email and phone number. |
| VPN Laboratory |
3402 W. Holland Ave. #101
Fresno, CA 93722
|
559-276-0403 Fax: 559-276-0422 |
$13 for organic matter analysis // $61.25 for fertility essay + organic matter |
Samples can be mailed to the laboratory. |
Last updated: 8/22/2022
How can I interpret my soil test results?
What do my results mean?
The laboratory that tests your soil will often give you some interpretation on the results, and you can ask if they have handouts/further information specific to your crop. This is a good starting point to breaking down the numbers in your report.
If you tested soil from an orchard or vineyard, here is a short guide to interpreting your results.
If you are concerned about soil salinity, the UC Salinity Management website will tell you if the salts in your soils are affecting the plant growth and yield for your specific crop, as well as recommended salinity management practices.
Other resources like SoilWeb are a great tool to help identify the basic soil type found in your fields. They even give information on how your soil type/texture will affect water infiltration and holding, nutrient cycling, and soil pH.