blinks when
your plant is

THIRSTY-LIGHT – know when to water houseplants and potted plants

know when to water
your potted plants

How to measure moisture and humidity in potting soil with the thirsty light

How to use the Thirsty Light?

Improper watering kills or injures houseplants more than any other cause. Over-watering is just as harmful to your plants as under-watering. The Thirsty-Light is designed to help you monitor your plant's moisture so that you know when it's time to water. It can be used in two ways:

Leave-In Method

Use one Thirsty-Light for each plant, leaving it in the pot. This is the most convenient way to use it because the plant's soil moisture level is constantly monitored.

Quick Check Method

Share one Thirsty-Light among several plants, moving the probe from one plant to the next. The digital sensor tests conditions once every second, so each pot's soil moisture can be assessed quickly and accurately.

How does the Thirsty Light alerts you when it's time to water again

Turn the power switch to the “ON” position. The Thirsty-Light's LED Alert light will emit a single long blink.

  1. Insert the Thirsty-Light into the soil so the pod and approximately 1"(2.5cm) of the probe is above the soil line. Choose a location between the edge of the pot and the plant stem with good visibility of the LED Alert.
  2. The LED Alert blinks to tell you when the soil is dry (see Moisture Signal Chart). It blinks faster as the soil gets drier.
  3. Leave-In Method: leave the Thirsty-Light in the soil with the power switch in the “ON” position. The LED Alert will notify you when it's time to water again. Pay attention – you may need to adjust the probe (see Adjusting Performance section). If you've used the Quick Check Method: when you are finished checking the soil and watering, turn the power switch clockwise to the "OFF" position.


regular blinkung soil is dry
time to water
double blink + long pause completely dry soil
water thoroughly
triple blink + long pause low batteries or
bad switch contact
no blinking soil is moist, check again later.
Batteries are dead replace batteries
The Thirsty Light uses Drypoint technology
which has 5 levels of sensitivity and
makes the LED blink faster as the soil gets drier.