Interpreting Soil Test Results
Now that you have calculated the percentages of soil components, you have a general idea of your soil type and can choose plants that are well-suited to your native soil. If you’d like to get more scientific about it, consult the soil pyramid below to find the scientific classification of your soil based on the percentages of each layer.
Here’s how the soil tests I conducted came out:
- Farm Soil: (sandy loam) 70% sand, 20% silt, 10% clay
- Yard Soil: (sandy clay loam) 50% sand, 25% silt, 25% clay
In my experiments, it appears that the farm soil is sandy loam, while the soil in my yard is sandy clay loam. Both soils can benefit from improvement in both texture and fertility. Neither contain much in the way of organic matter, which fits with the low nutrient levels in my chemical soil analysis.
I was surprised to find that my home soil had such a high sand content, but I took the sample from an area that was amended with trucked-in soil during a grading project. Multiple samples – from different spots – would give a better overall picture.
As a comparison, I also did a jar test with some commercial potting mix as well (see photo at top), which is very high in organic matter and sand, making it perfect for the delicate roots on potted plants.
Improving Soil Texture
So what now? The good news is, adding organic matter will help all types of soil. It makes clay soils looser, helps sandy soils retain water and nutrients, and generally improves the texture and drainage of all soil types.
Organic matter such as compost, leaf mold, and humus add both soil particles and organic nutrients that balance out soil types. After amending your soil, conduct another jar test to see how your soil measures up, then add more or less organic matter next time to even out the ratios.
Further Information
- Soil Test (video)
- DIY Soil Drainage Perk Test for Your Yard (article)
- DIY Soil pH Test Using Household Ingredients (article)
- Top-Dressing to Improve the Soil in Your Yard (article)
- Soil Types and Testing (rain.org)
- What is Soil? (lawnlad.com)
Thank you for the pyramid and testing process. I knew my soil was heavily sanded but testing helped me to see that the sand content was over 60%! This knowledge will greatly assist me with the amendment process,
We humans need to butt out on ‘making soil better’…soil is soil, ALL soil is great soil when we humans learn how to manage. Adding sand, compost…is ridiculous.
Stay with the type of soil you have on your site. NEVER use garden soil for potting soil.
Arghhh! Listen up all of you. Hate to be a damn know it all but here goes! The only way to improve ANY soil is by dumping DECOMPOSED organic matter right on the surface. PERIOD. Learn firstus what kind of soil you have. The texture test. Then learn how to make plant beds the first and only time. Learn what decomposed means and what kind of decomposed mulch you have access to…learn about the chemistry necessary for plants that IS NOT IN THE SOIL normally. That we HAVE to add to be able to grow plants we want, where we want, when we want and why we need them. Not happening in nature believe me. Nature does not allow excess chemistry (you people insist on calling them nutrients which means food and plants make their own food, fertilizer is NOT FOOD), to exist in soils. POPULATION CONTROL.
We humans will never be able to CHANGE the soil in our gardens to see any success. Use only potting soil for potted plants and planter type situations (sterilized) and potting soil has very little actual soil in it! Learning how to manage soil is critical.
And ‘heavily sanded’? I moved to a place with pure pumice for soil. Works just fine. All I do is double dig the beds ONE TIME and add decomposed organic matter to the surface…I’ve had excellent crops and success from the very first season. I also use balanced fertilizers and know how to manage the different formulations and know something most people do not…LESS is Best, MORE is Death and NONE is dumb. Plants tell us what they are missing or have in excess. We gardeners need to learn what that looks like for different plant types.
I never FEED plants, I make sure they’ve got a bare minimum balanced fertilizer added once my starts are up potted to 3″ pots from the seed starting trays where ONLY potting soil is used. 1″X2″. Up potting is the time to add fertilizer (5-5- 5) is safe Do you guys know when to make sure that first number should be lower than the other two? I rarely use fish emulsion because that needs to be added to the fertilizer program, it is not a balanced fertilizer.
The ONLY amendment we humans should do to our soil other than double digging and forming plant beds with little trenches and compacted before planting is simple DECOMPOSED compost, organic matter. Decomposed.
This FEEDS the life in the soil. If the matter is not decomposed the decomposers need nitrogen to finish their job and they get first priority over plants. Very very little is ever left over from decomposition. This stuff is critical to feed the soil life. Without soil life your soil becomes compacted and not conducive for plants. All soil life needs decomposed organic matter to eat. They go up to the surface and eat. Go back down into the top soil, 4 – 6 inches and poop it out. Mixing this into whatever soil you have; sand, clay, loam. All soils need this organic matter to be able to support plants, buffer pH so that what chemistry you do add is made available to plants.
There IS NO OTHER amendment anyone should ever ever add to soil. Lime if IF the pH is too low for the plants one wants to grow. Lawns need a slightly higher than neutral pH. A test is critical FIRST before adding lime. Fertilizer should be on a plant to plant basis. Not rocket science but there are these ‘trends’ for no fertilizer that are just wrong!
The recipe for concrete; Clay, sand, gravel, lime, gypsum, water and ROTATION. Think about this. Clay is fantastic soil! You just need to learn proper management! Sand is fantastic soil and it has it’s very own special management techniques. Just find a great source of decomposed organic matter and dump on the surface. Also great to control weeds, suppress weeds.
Thanks for sharing your thoughts with the TodaysHomeowner.com community, stormy!
Take care. 🙂