The best homemade pH tester you can make uses red cabbage from your kitchen. This veggie holds natural dyes that shift color based on how acidic things are. Purple means neutral, pink means acidic, and green or blue means your soil leans alkaline.
I made my first red cabbage pH test on a rainy Saturday last spring. I chopped up half a head of purple cabbage and boiled it until the water turned deep purple. The smell was strong but the result was a jar of bright violet liquid that worked as a DIY pH indicator for weeks in my fridge.
The science behind this test comes from chemicals called anthocyanins. These natural pigments react to hydrogen ions in your soil water and shift color. The color change tells you which side of neutral your soil sits on. Pink shades point to acidic soil while blue or green shades mean alkaline.
You can make pH test home style with simple kitchen tools and about twenty minutes of your time. Chop one cup of red cabbage into small pieces. Boil in two cups of distilled water for about ten minutes. Strain out the cabbage pieces and let the purple liquid cool down. Store in a clean jar away from light.
To test your soil, mix a scoop of dirt with distilled water and let it settle for an hour. Pour off the clear water on top into a small cup. Add one tablespoon of your cabbage indicator and watch the color shift. Compare what you see to a color chart to read the rough pH range.
I tested soil from three different beds with my cabbage juice last year. The raised bed turned light pink which matched the lab result of pH 6.2 pretty well. My native soil patch went blue green which told me the pH was up around 8 before I even sent samples to the lab.
This test works great for quick checks but cannot give you exact numbers. You might see pink but have no way to tell pH 5.0 from pH 6.0 just by looking. For amendment decisions, get a proper lab test or meter that shows you specific numbers.
Kids love to help with this project and learn some science at the same time. The color changes are dramatic enough to hold their attention. Just keep in mind that your homemade tester gives you a starting point rather than a final answer for your garden.
Read the full article: Testing Soil pH: A Complete Guide for Gardeners
