How a soil pH meter works?

The research and development of portable soil pH tester has two main design methods. They either include an electrode in the body of the device (all-in-one design), such as a soil PH meter; Alternatively, electrodes are connected to the body via wires, such as a soil PH sensor.

Irrespective of the design, the principle behind the technology is the same. The pH electrode that takes the pH measurement consists internally of a reference electrode, reference solution, reference junction and a glass bulb with a hydrated gel layer. When your electrode is submerged in the diluted sample or pressed into the soil an electrical current is triggered. The tester then calculates the charge of the reference solution inside the bulb and compares it to the soil medium outside of the gel layer. This comparison results in a pH measurement which is displayed on the pH meter’s screen – all within a matter of seconds.

How to Test the Soil pH With a Digital pH Meter?

Gardening is like gambling — you plant and hope for a big payoff in produce or flowers, often sweetening the pot with an investment in soil amendments. Testing your soil’s pH improves your odds of garden success by letting you know ahead of time if a plant is likely to thrive as is or needs specific changes to soil chemistry. When soil pH is too high or too low for a plant, either the plant can’t access nutrients already in the soil or the nutrients become toxic to the plant. A digital soil pH meter takes the guesswork out of matching plant to site and tells you which soil amendments are needed in a matter of seconds.

1.Dig out the top 2 inches of soil with a shovel in several locations in your planting bed, because soil pH can vary widely, even in the same garden.

2.Loosen the soil with a garden trowel to about 5 inches deep and add a scoop to the bucket, making sure to get soil from more than just the top layer.

3.Add soil from each sample site to the bucket.

4.Mix all the soil samples together thoroughly, removing any rocks or pieces of debris.

5.Measure out 2 cups of the mixed soil and put it in a clean container.

6.Add distilled water to the soil until it is damp enough that you can firmly compact it inside the container.

7.Clean the probe on the digital soil pH meter with the included pad or a paper towel, wiping away from the tip.

8.Turn your digital soil pH meter on and insert it into the soil, twisting it to make sure it has good contact with the soil. Keep it away from the bottom of the container.

9.Let it sit in the soil sample for the amount of time required by the manufacturer, usually about 60 seconds.

10.Note the reading and make any changes to your soil that it indicates. Soil pH is expressed on a 14-point scale, with 7.0 being neutral. Numbers higher than 7 are considered alkaline and lower numbers are acidic.

What to look for when selecting your soil pH meter

There are many types of soil pH meters in different shapes and sizes to suit all applications, ranging from meters for the avid home gardener to large agricultural operations. When selecting the right soil sensor for you here’s a list of things to consider.

1, Portability. Will you need a pH meter that is lab-based, field-based or a combination?

2, Method. Can soil be sampled directly or is dilution required?

3, Functions. Are other built-in functions required? For example, soil moisture and conductivity.

4, Length of the probe. The minimum sample depth is generally 20cm. Different plants and crops require measurements to be taken at varying depths.

5, Accuracy. Traditionally direct soil sampling is less accurate than the dilution method.

6, Calibration. Does the device come with any buffer solutions to calibrate your meter?

7, Sampling time. How long does it take to get a result?

8, Device and electrode durability. Take care as direct ground measurement can damage the glass within an electrode.