Organic Soil Amenders, Inc offers
products, spreading, blending and various soil testing.



We have the equipment to service your spreading needs for all our products. From the self-contained GMC Topkick to the Versatile 310 tractor and Tebbe spreader- we can handle it. Got 1000 acres of wheat? We can do it!  Spreading fees are per-acre. Delivery fee may apply. (Currently, we do not supply any rental equipment.)


We can custom-blend any of our products to meet your soil needs. Blending fees are per ton, per product. View our products now!

Soil Tests

OSA Soil Testing ServiceTesting your soil provides a starting point- an audit of what you have to work with and what should be changed. Let us help you choose which testing method will best meet your needs. The charge for one basic soil test with lab results and interpretation will be refunded with your minimum purchase of one load or more of gypsum.

Concurrent testing helps in the management of nutrient applications. It provides a gauge to guide and fine-tune your inputs for the best results. A comprehensive soil test will show more than just NPK. It should also show nutrient levels- too little or too much, as well as:

    • CEC (cation exchange capacity- which tells how easily elements will move through your soil)
    • Base Saturation (tells how full your pantry is with the base elements- Ca, Mg, Na, K)
    • Soil Characteristics (pH, organic matter, soluble salts)

Custom Crushing

OSA Custom Crushing ServiceOur portable crushing and screening plant offers various options to meet your ag needs. A set-up fee and mileage is payable in advance for crushing limestone, gypsum or other soft-rock products at your location. Conditions apply, and we do not service road rock.

Brix Testing

A brix test is commonly used in the wine making industry to measure sugar levels in grapes.  A refractometer, used for brix testing, is also used to measure leaf sap right in the field. Studies have shown that plants with low brix readings are magnets for predatory insects. Very healthy plants are not attractive to insects and are not consumed by them. 

An effective brix reading for plants will run from 1 to 20.  At a level of just 1 or 2, plants will be consumed by insects and have no chance for survival. A 3 to 7 reading indicates insects are still very interested in these plants, but there is a margin of survivability.  At an 8 to 12 reading insect resistance begins, and at the 13 to 20 level the plants/crops are very healthy and the food produced for animals and humans is good.

If your plant or crop brix reading is below 9, it’s time to do further soil and plant testing to see what’s missing. (For a more detailed discussion, see the article by Thomas Dykstra in the September 2019 issue of Acres USA magazine.)

Brix testing is included with an extended consultation appointment.

Paste Test

This test provides a measurement of which nutrients are freely available for plants at the current time. At the lab, your soil sample is mixed in distilled water and agitated. The water is drained off, and then tested for what is suspended and in solution. The nutrients shown to be in this solution are immediately available to plants-  no breakdown by microbes or plant acids are needed. For a small fee, a paste test can be added to any basic soil test sent to the lab.

Compaction Test

A soil probe tool with its pressure gauge provides a measure of compaction. If there are no spaces for air or water, then irrigation, rain and nutrient applications can run off and be lost. If there is a sub soil compaction layer such as hardpan, a plow-pan, or caliche layer (hard undissolved salts) a compaction test can identify potential problems and further treatments can be applied.


OSA consultingAre you starting out with new ground or first time crops? Trying to remediate a poorly performing pasture or cropland? We can help you choose the correct test and treatment to remedy these and more issues. We can also aid in diagnosing and solving many other challenges with your soils, crops and weeds. First hour is free of charge for new customers!  Give us a call at 509-935-7154 or send an email. We’d love to help.

OSA Products

Take a look at our products today!

Want to learn more about soil?

Soil is the basic building block of life. Learn about what to look for in your soil today!

Interested in learning more?

Browse our list of references in our Soil Library