Plants use sugars to tell the time of day, according to research published in Nature today.
Plants, like animals, have a 24 hour 'body-clock' known as the circadian rhythm. This biological timer gives plants an innate ability to measure time, even when there is no light - they don't simply respond to sunrise, for example, they know it is coming and adjust their biology accordingly. This ability to keep time provides an important competitive advantage and is vital in biological processes such as flowering, fragrance emission and leaf movement.