Test garden soil for free with products commonly found in the kitchen such as baking soda, vinegar and red cabbage. Soil pH determines the minerals and nutrients available to the plants. Some plants are equipped to survive in alkaline soil. Other plants thrive in acidic soil.
Gradually improve the soil by bringing the pH to neutral levels and adding nutrients with compost and organic mulches. Or, choose plants specific for the soil's current acidic or alkaline conditions.
Take samples from different parts of the garden amounting to 1 cup. Put two spoonfuls of soil in a container and pour 1/2 cup of vinegar. If it fizzes, the soil is alkaline. If it doesn't fizz, put two spoonfuls of soil into another container and add water until it becomes muddy. Add 1/2 cup of baking soda. If it fizzes, the soil is acidic. If there's no reaction after the second test, the soil is pH neutral.
Another way to test the soil is with cabbage water. Simmer one cup of chopped red cabbage in 2 cups of water for five minutes. Then, remove it from the heat and let it sit for 30 minutes. Strain the bluish-purple liquid and pour it in a transparent bowl. Add two teaspoons of soil, stir well, and wait for 30 minutes. The cabbage turns pink if the soil is acidic, and it turns bluish-green if the soil is alkaline.