Why measure water potential?

Why measure water potential?

A comprehensive look at the science behind the water potential measurement. Understand water potential theory and application. Explore the difference between water potential and water content. And learn the key components of water potential: matric potential, osmotic potential, gravitational potential, and pressure potential.


An ecologist installed an extensive soil moisture sensor network to study the effect of slope orientation on plant available water. He collected reams of soil moisture data, but ultimately he was frustrated because he couldn’t tell how much of the water was available to plants.

He’s not alone in his frustration. Accurate, inexpensive soil moisture sensors have made soil moisture a justifiably popular measurement, but as many people have discovered, a good hammer doesn’t make every soil water problem a nail. Water content can only show how much water there is. Hydraulic conductivity shows how fast water can move. But water potential shows whether it will move and where it’s going to go.

Click on the links below for a comprehensive look at the science behind water potential measurement.

Or want it all in one convenient place?

Download the “Researcher’s complete guide to water potential”

Six things you need to know

  1. An introduction to water potential: Watch our latest webinar to learn the basics of soil water potential and how to use it. Read more
  2. Defining water potential: Discover the science behind the measurement—understand the different components of water potential. Read more
  3. How to measure water potential: Learn current methods for measuring water potential and the pros and cons of each method. Read more
  4. Water potential—a little history: Explore the history of water potential measurement. Read more
  5. Water potential in action: Learn how water potential and water content work together to help researchers understand the bigger picture. Read more
  6. Water potential and soil moisture release curves: What they are. Why you need them. How to use them. Read more


A photograph of the TEROS 21 soil water potential sensor
Figure 8. TEROS 21 soil water potential sensor.

Master the basics

In this webinar, Dr. Doug Cobos differentiates water potential from water content, discusses the theory, application, and key components of water potentialmatric potentialosmotic potentialgravitational potential, and pressure potential.

Take our soil moisture master class

Six short videos teach you everything you need to know about soil water content and soil water potential—and why you should measure them together.  Plus, master the basics of soil hydraulic conductivity.

Watch it now

Use water potential to optimize irrigation

Download “The complete guide to irrigation management”

Watch more water potential webinars

The following webinars cover water potential instrument theory, including the challenges of measuring water potential and how to choose and use various water potential instruments.


Our scientists have decades of experience helping researchers and growers measure the soil-plant-atmosphere continuum.

Measurement insights

See all articles

How to Measure Water Potential

Compare current methods for measuring water potential and the pros and cons of each method.


Defining Water Potential—What It Is. How to Use It.

Understand the different components of water potential and how to use them. Water potential is the energy required, per quantity of water, to transport an infinitesimal quantity of water from the sample to a reference pool of pure free water.


How to model plant available water

Dr. Gaylon Campbell, world-renowned soil physicist, teaches what you need to know for simple models of soil water processes.


Case studies, webinars, and articles you’ll love

Receive the latest content on a regular basis.

icon-angle icon-bars icon-times