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Hack to Test Your Soil PH

Do a simple pH test on your soil with baking soda. Your plants absorb the minerals found in the ground through their roots. If the soil is too acidic or alkaline, it hampers this process. Conduct a simple home experiment using baking soda and vinegar to test your soil’s pH levels.

Use Baking Soda & vinegar to Test Garden Soil

  • 1/2 cup of vinegar
  • 1/2 cup of water
  • 1 tablespoon baking soda
  • 2 soil samples from your garden
Place the two soil samples into small cups. Add the vinegar to one of the cups. If the soil bubbles, the soil is alkaline.

This means your soil has a pH level of seven or more. If it doesn’t bubble, use the other soil sample to test the acidity. Add the baking soda to the water and pour the solution into the second cup. If the soil bubbles, you have acidic soil with a pH level of seven or below.


Descriptive terms commonly associated with certain ranges in soil pH are:

Descriptive terms commonly associated with certain ranges in soil pH are:
  • Extremely acid: < than 4.5; lemon=2.5; vinegar=3.0; stomach acid=2.0; soda=2–4
  • Very strongly acid: 4.5–5.0; beer=4.5–5.0; tomatoes=4.5
  • Strongly acid: 5.1–5.5; carrots=5.0; asparagus=5.5; boric acid=5.2; cabbage=5.3
  • Moderately acid: 5.6–6.0; potatoes=5.6
  • Slightly acid: 6.1–6.5; salmon=6.2; cow’s milk=6.5
  • Neutral: 6.6–7.3; saliva=6.6–7.3; blood=7.3; shrimp=7.0
  • Slightly alkaline: 7.4–7.8; eggs=7.6–7.8
  • Moderately alkaline: 7.9–8.4; sea water=8.2; sodium bicarbonate=8.4
  • Strongly alkaline: 8.5–9.0; borax=9.0
  • Very strongly alkaline: > than 9.1; milk of magnesia=10.5, ammonia=11.1; lime=12


• When the pH is not at the proper level the plant
will lose its ability to absorb some of the essential
elements required for healthy growth.

• For all plants there is a particular pH level that will
produce optimum results. This pH level will vary
from plant to plant, but in general most plants
prefer a slightly acid growing environment
(between 5.5-6.5),

• When pH rises above 6.5 some of the nutrients and
micro-nutrients begin to precipitate out of solution
and can stick to the walls of the reservoir and
growing chambers.

• For example: Iron will be about half precipitated at
the pH level of 7.3 and at about 8.0 there is virtually
no iron left in solution at all.

• use the nutrients they must be dissolved in the
solution. Once the nutrients have precipitated out of
solution your plants can no longer absorb them and
will suffer deficiency and death if left uncorrected.
Some nutrients will precipitate out of solution when
the pH drops also.