Soil Testing
When and how often should I test my soil?
We suggest testing your soil annually, a few months prior to planting a garden, establishing perennials, or before the optimum time for fertilizing lawns to allow ample time for the lime to react with the soil.
Will you collect soil samples from my property for me?
We do not have the staff to visit your site directly; however, please contact your Local Extension Agent for consultation.
How can I get my sample to you?
You may drop your sample by the lab or mail your sample, analysis form and payment directly to us at: 171 Old Cherry Rd, Clemson, SC 29634.
Drop it off at your local County Extension Office.
Purchase a mailer kit. The cost is $15 and includes the fee of one standard soil test. With this purchase, we will mail a package containing 1 soil bag, analysis form and postage paid return envelope to you.
Can I bring samples directly to the lab?
Yes, if you prefer, we encourage anyone in the area to come by the lab directly. We have a drop box for all samples located at the loading dock near the back of our building. If assistance is needed, you may ring the bell and speak with a lab staff member during business hours (Mon-Fri, 8:00am-4:30pm).
How much soil do I need to send?
2 cups of soil per composite sample is required for a standard test
1 quart of media is required for a soilless mix test
Please allow your soil to air-dry overnight before submitting to the lab.
Where can I find the sample forms to submit with samples?
Please write legibly or fill in the form using your computer. This is the information we use to get your report to you.
For information on how to collect a soil sample, visit our webpage here
For instructions on how to complete the Soil Analysis form, visit our webpage here
What is a Sample Label or Grower Sample ID?
This field is assigned by the customer so they can identify which sample the results are for. There is a 10 alpha/numeric character limit for soil and 8-character limit for other analyses.
How much does a standard soil test cost?
$6. This is the most requested test which includes pH, buffer pH lime requirement and extractable P, K, Mg, Ca, Zn, Mn, Cu, B, Na, CEC (cation exchange capacity), and % Base Saturation.
How do I pay for my test?
Acceptable forms of payment are cash (if dropping off in person), check, money order and credit card. We do not accept payments over the phone.
If leaving your sample at an Extension Office, your payment will be accepted there.
Do I need an account to send samples for testing?
No. An account is not required to submit samples to our lab for testing. Accounts are established for customers who are submitting a minimum of 100 samples per year.
If sending your sample directly to the lab, acceptable forms of payment are cash, check, money order and credit card. We do not accept payments over the phone.
Payments are also accepted at your local Extension Office upon sample drop-off.
How long will it take to get my results?
Standard soil results are typically available between 3-10 business days. Additional tests for soils may take up to 7 additional business days.
Irrigation Water, Plant, Feed, Waste and Compost results are typically ready within 5 business days.
How do I access my results?
You will be emailed a link to your report from the lab when the results are complete. A mailed copy can be mailed to you for an additional $1. You can also access your results on the Report Distribution Webpage using your personal login credentials.
Who do I contact with questions about my soil tests results and/or recommendations after receiving my report?
An agent with your local County Extension Office will be able to assist you, or you may contact HGIC for home and garden questions.
Farmers are encouraged to reach out to their local Extension Office.
What is Buffer pH and how is it used in my analysis?
Buffer pH is an indicator of soil’s resistance to pH change.
We add a buffer solution, which reacts like a fast-acting lime, to the soil/water slurry, and then we measure the Buffer pH. Both the Soil and Buffer pH measurements are used to determine the lime requirement needed to adjust the soil’s pH to a desired target pH for optimal crop growth. The illustration and table below explain the meaning of the measurements for example soils 1 & 2.
| Soil Property | Soil 1 | Soil 2 |
|---|---|---|
| Soil pH (active acidity) | 5.5 | 5.5 |
| Buffer pH | 7.65 | 7.85 |
| Buffer pH - Water pH | Smaller difference | Larger difference |
| Buffering Capacity | greater | lesser |
| Reserve Acidity, CEC | larger | smaller |
| Lime Requirement | more | less |
How can I convert the fertilizer recommendation to something I can purchase in the store?
You can use this calculator if you need to convert from the fertilizer recommendation to something available at your local retailer. Alternatively, you may contact HGIC or your local County Extension Office for assistance.
To calculate the limestone rates for raising soil pH, this Lime Rate Calculator is available.
You can use this Liquid Fertilizer Calculator to easily calculate nutrient composition and resulting density of liquid fertilizer solutions for soluble fertilizers.
The Fertilizer Blend Calculator will evaluate different blends for meeting NPK application requirements in a cost effective manner for agriculture, horticultural, silvicultural, turfgrass, and home lawn/garden producers.
Do you test for toxins or pollutants in the soil?
No, we do not. We perform nutrient and pH testing to provide recommendations for plant growth.
Do you perform perc tests?
Perc (or percolation) testing is not performed by an agricultural laboratory. Please contact S.C. DHEC at 1-803.896.0640 for information on perc testing in South Carolina.
