Plan the perfect garden with our interactive tool →

How Does Infrared Heat Signature Work on Plants?

seeds image by Jane from

Infrared scanners can detect the amount of heat objects are giving off. Every living thing gives off a distinct amount of heat known as a heat signature. Heat signatures have many uses with plants. Some innovative applications have been developed using this measure.

Police Investigations

In states in which marijuana gardens are illegal, police use infrared scanners to detect illegal crops. As police fly a helicopter over a location, they run their infrared scanners to determine if the heat signatures from plants are from marijuana or other plants. Additionally, police study heat signatures from grow lamps used for faster marijuana production.

WaterLink Project

In the U.K., water for plants is becoming a precious commodity as of 2011. One way of saving water and ensuring that plants receive only the water they need is leaf thermal imaging. As a plant undergoes water stress. it shuts down the stomas on its leaves and begins heating up. This heat can be picked up by thermal scanners and farmers are then able to specifically irrigate those crops.

Seed Viability

Planting non-viable seeds wastes a farmer’s time and resources. With infrared heat imaging, farmers are able to sort through seeds and determine which seeds are viable. During germination, seeds are soaked in water. Once the seeds absorb water, their thermal heat signature changes and becomes slightly cooler. Seeds with a higher infrared heat signature are not viable and can be sorted out.

Plant Pathogen Interactions

One breakthrough in technology as of 2011 is saving farmers thousands in lost crops due to disease. Infrared studies have begun recording the heat signatures from diseases in plants. Pathogens such as TMV in tobacco can be sensed before the pathogen is visible to the eye and contagious to the surrounding plants.

Garden Guides