Does anyone have any methods for doing soil tests on the farm without having to send it away for analysis? I am particularly curious for methods on general nutrient levels and pH. It is fine if it is a more general than precise measurement.
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@Ruben_Langston_Smith is the resource you created for simple, in-field measurements publicly available yet? Ruben highlighted in his guide, one method using red cabbage for pH approximation that was pretty cool! Here’s a different resource that highlights this concept: [Using red cabbage as a pH indicator]. (red cabbage for pH detection soils - Search Videos. I think you’d need to have a filtrate (soil water solution) to utilize this which you can do by shaking soil in DI water for 5 minutes then running it through coffee filter paper.
Quinn, I’ll add a couple of resources below that Robert, Ruben, and I have been synthesizing. No reason not to share them in their current form, though! You’ll notice that most nutrient and pH in-field discussion is about plant nutrient deficienty detection which is a really vital skill for farmers to develop! Patrick wrote an article about in-field detection you can find here: Diagnosing Crop Nutrient Deficiencies in the Field | ECHOcommunity.org
Soil Health Assessment Tool within TAPE: Tool for Agroecology Performance Evaluation (TAPE)
Soil Health Assessment Tool from Cornell: [Manual | Cornell Soil Health] (Manual | Cornell Soil Health)
Soil Health charts Andy developed: 3. Soil Health Assessment Charts.pdf (305.1 KB)
Hi Quinn — great question.
You can get a general sense of pH and nutrients without lab work using simple pH meters/strips and basic NPK test kits. They’re not highly precise, but helpful for quick field checks.
A great, accessible option is Graham Shepherd’s Visual Soil Assessment (VSA), which uses field observations (structure, color, roots, worms, etc.) to score soil health with minimal tools.
Guide link: https://orgprints.org/id/eprint/30582/1/VSA_Volume1_smaller.pdf
There are plenty of other DIY resources online, but VSA is one of the best places to start.
I am not sure if this has been mentioned but I really like the pH test system “quick and dirty” (pun intended). You can look up online the type of soil you have in the area or talk to your government extension people to learn what you can about your soil types in your area. If you suspect your soil is basic (drier regions are often more basic which is less common than acidic…. Then you add a little vinegar to your soil and then if it reacts vigorously then the soil is very basic or the pH is a higher number. If it reacts only a little then it is likely close to neutral but of course above some. If it does not react at all then the soil is neutral. If you suspect your soil is acidic which is most common in higher rainfall areas, particularly those that do not have limestone as bedrock then add baking soda but when you are looking for baking soda in other countries besides the US ask for bicarbonate. Follow the same testing as I have outlined for vinegar. Now you will want to notice differences between different depths and soil profiles which will have different pHs. Organic or more black soils are going to have lower pHs and lighter colored soils may be more basic but that is not a rule but just what is common. Also be sure to use the latest updates of apps that give you information on your soils from photographs. These can offer a little help as well but may not be that accurate and only as a part of the mix of information you collect. Chat GPT is a good resource if you ask it to search the internet for the soil in your area. I would give Chat GPT a pin drop of your location so it can be more accurate. Also tell Chat GPT the results of your test and what the soil app is saying as a result of the picture you fed it so it has more information. You should also be creating a ribbon with the soil to see how much clay it has. You can google how to do that. I just smash the soil between my fingers to see how long the ribbon can extend before it breaks. I maintain the ribbon about 1/8 inch wide and keep playing it out and if it heavy clay it will go out 2 or 3 inches and if it breaks short it is heavier in sand.
Most all garden shops and hardware stores, at least in the USA, sell electronic inexpensive soil meters.
My experience with these cheap meters has been poor.
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