Measurement Of pH In Plant Tissue 

LAQUAtwin is a series of pocket ION meters. Using Ion Selective Electrode (ISE) technology, they are available for measuring Conductivity, Calcium, Nitrate, Potassium, Sodium, Salt concentration and pH measurement. Using just a tiny amount of sample, the LAQUAtwin proprietary flat sensors can quickly and accurately measure the values of the chemical parameters in the field.


It is often necessary to measure the pH of plant tissue to determine plant health. At pH values above 6.4 plants can be prone to insect attacks and at pH values below 6.4 plants can be prone to specific diseases. Thus an optimal pH of 6.4 is desired. Whilst laboratory soil and tissue tests are beneficial tools, they often do not yield results for days or weeks. We can thus use an alternate method of diagnosing plant health using the LAQUAtwin pH meter.

The LAQUAtwin pH meter is used to determine  the pH of plant tissue. This is an easy and quick method used to  ensure that plant tissue is at the optimum pH.


To measure, take a few leaves, roll them into a tight ball and squeeze out a few drops of sap using a garlic press. Be sure to use a good quality stainless steel garlic press.

Generally, the mature leaves of the plant give the most accurate picture of the plant’s health.

The plant tissue can be measured using the LAQUAtwin pH meter. The plant tissue has sufficient moisture and can thus be placed on the sensor of the pH meter and measured. If the pH value is more than 0.5 away from the optimal 6.4 value, we can adjust as follows:

If the pH is >0.5 higher than 6.4: add small amount of phosphate fertilizer
If the pH is >0.5 lower than 6.4: add small amount of calcium/potassium fertilizer

After a week, repeat the test; ensure the pH of the plant tissue is close to pH 6.4 for optimal plant health.

Results and Benefits

The use of the Horiba LAQUAtwin pH meter to ensure an optimal pH of 6.4 in plant tissue will encourage healthy plant growth and prevent insects and diseases attacking the plant.
The LAQUAtwin pH meter is small and compact; convenient to carry around in your pocket for easy on-site testing. Its easy-to-use interface is simple for anyone to use the LAQUAtwin pH meter.

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