Plan the perfect garden with our interactive tool →

How to Read a Plant Moisture Meter

A plant moisture meter has a brass or steel probe attached to a hand-size box with a gauge that measures varying levels of moisture in the soil. Costing less than $20 (in 2009) and operating without a battery, a plant moisture meter can take the guesswork out of watering plants in the house or garden.

Confirm that the indicator arm on the face of the gauge is pointing to “Dry” (the default setting). Dry, Moist and Wet are the gauge's three levels, and each level is broken down using a numbering system: 1 to 3 (Dry), 4 to 7 (Moist) and 8 to 10 (Wet).

Insert the probe into the soil close to the base of the plant. The probe is designed to read moisture content at the root level. Most plants will have an extensive root system, so push the probe halfway into the pot to be assured of being in the middle of the roots. For very large pots, you may need to push the probe into the soil until the gauge touches the soil.

  • A plant moisture meter has a brass or steel probe attached to a hand-size box with a gauge that measures varying levels of moisture in the soil.
  • For very large pots, you may need to push the probe into the soil until the gauge touches the soil.

Read the face of the gauge, which should have immediately indicated the level of moisture. Some plants require a continuously moist soil or recommend that you water once the soil is completely dry. Base watering decisions off the gauge reading and plant needs. You can leave the probe in place while you water the plant.

Use the numbers on the gauge to determine the plant's water usage and the needed frequency of watering without constantly using the gauge. For instance, if the gauge reads Moist 7 on the first check and seven days later the reading is Moist 4, you know the plant can go up to seven days without being watered. Conversely, if the gauge reads Dry after seven days, you know you need to water more often given the dramatic decrease in soil moisture.

  • Read the face of the gauge, which should have immediately indicated the level of moisture.
  • Use the numbers on the gauge to determine the plant's water usage and the needed frequency of watering without constantly using the gauge.

Rinse the probe and wipe dry after each use.

Tip

The frequency of watering plants will depend on the size of the pot, its location, whether it has a tray or internal reservoir, and how humid it is.

Related Articles

How to Use a Volt Meter to Check the Neutral & Ground
How to Use a Volt Meter to Check the Neutral & Ground
How to Test a Lawn Mower Battery
How to Test a Lawn Mower Battery
How to Water Sedums
How to Water Sedums
Soil Moisture Content Testing Methods
Soil Moisture Content Testing Methods
What Is Astm D1557?
What Is Astm D1557?
How Much Water Do Bell Peppers Need
How Much Water Do Bell Peppers Need
How to Bring a House Plant Back to Life
How to Bring a House Plant Back to Life
How to Adjust the Tracking on a Scag Mower
How to Adjust the Tracking on a Scag Mower
Are Chinese Palm Plants Poisonous to Cats?
Are Chinese Palm Plants Poisonous to Cats?
How to Treat an Aloe Vera Plant That Turned Yellow
How to Treat an Aloe Vera Plant That Turned Yellow
Garden Guides
×