There are plenty of gardeners that talk to their plants in the belief that it helps them grow. While plants aren't likely to be eavesdropping on our conversations anytime soon, they could be gathering different types of intelligence if a new DARPA program bears fruit. The agency is pursuing research into genetically modifying plants to turn them into self-sustaining surveillance sensors.

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The aim of the program is to genetically modify certain plants so that specific response mechanisms are triggered when they are presented with specific stimuli. It is suggested that existing hardware can be used to remotely monitor these responses so the plants could essentially be used as organic sensors. As such, the program won't seek to develop new hardware for this purpose, but rely on existing technologies that can already measure such things as a plants' temperature, chemical composition and reflectance.