Moisture meters take the guesswork out of watering

A moisture meter is a simple tool that can be useful for interiorscape technicians. It’s a helpful way to check the soil moisture level and gives us an extra edge in providing quality of care for interior plants. A meter is easy to use; all you need to do is insert the probe into the soil down to the active root zone of the plant and read the results on the gauge. Usually, this means two-thirds of the way down into a small pot or 6-8 inches in a large pot.

A benefit to using meters is that you can be assured that everyone within your company will be speaking the same language regarding soil moisture. A reading of “3” on a meter can only mean one thing, but what feels moist to one person may mean wet to another when your are using your finger as the gauge.

Because the moisture meter is a sensitive device, the following guidelines should be taken into consideration.

  • A moisture meter will last you about six months if you treat it kindly.
  • Check your meter regularly for accuracy by putting your meter’s probe in your bucket of tap water. If the needle immediately goes to the highest reading, it’s still in working order. Probes do wear out, and if the reading is only part way up the scale, you know it’s time for a new meter.
  • Gently push or wiggle your meter through the media, especially if the media is cinder soil so as not to damage the tip.
  • Sometimes the meter is difficult to push in because there are a lot of roots. Don’t worry about damaging the roots; think of it as aerating the soil and letting more oxygen into the roots.
  • Insert the meter in two or three different locations to help you determine if all areas of the root ball are getting water. Note the readings at different depths, as well.
  • Leave the meter in the soil as you add water so you can “see” the water travel through the soil as the gauge moves upward.
  • The tip of the probe generates a very small current of electricity when it touches the salts in the water. If you are using water that is alkaline or testing a plant you suspect has a high salts content, you might not get an accurate reading.

Soil probes help judge moisture in containers by gathering samples of media from different levels within a pot. Follow these guidelines when using soil probes on interiorscape plants:

  • As with a moisture meter you should gently push or wiggle your probe through the media. Jamming it in can damage your probe!
  • Use sturdy metal probes on plants with dense root systems and with hard packed media such as lava rock or clay. Lighter plastic probes work well in peat-based media.
  • Take samples from several spots around the container; you’ll not only get a more accurate picture or the overall moisture content, but aerate the media, as well!
  • Sterilize probes used in pots infected with stem or root rots to prevent the spread of microorganisms.
  • Clean metal probes with a plastic scrub brush and soapy water. Dry and then wipe with lubricating oil. Replace bent or broken plastic probes.

Proper soil moisture levels are important for the health of your plants so use that moisture meter well!