When growing frost-tender plants in cold frames, greenhouses or even window wells, it is critical to know what range of temperatures your plants are subject to.
This thermometer will do just that. The operating mechanism is a bimetal strip that bends one way if heated, and the opposite way if cooled. The red marker is pushed to the right as temperature rises, and the blue marker is pushed to the left as temperature drops. Each marker rests at the minimum or maximum temperature marking, shown in both Fahrenheit and Celsius, until reset by hand.
The 5" diameter case has a teardrop aperture in the back for hanging it on a screw or nail on a wall or fence.
An ideal gift for people who want to know just how hot or how cold it gets each day, whether they are gardeners or not. Good value for the money.