Photograph by HANNAH HARDY, UNIVERSITY OF QUEENSLAND
Photograph by HANNAH HARDY, UNIVERSITY OF QUEENSLAND
MagazineBreakthroughs

What Happens When Plants Are Exposed to Near-Constant Light?

Hint: It’s called speed-breeding.

This story appears in the May 2018 issue of National Geographic magazine.

Fields of wheat and barley would grow faster if the sun didn’t go down at night. So an international group of scientists is essentially keeping the sun’s light on, as part of a method to “speed breed” plants. LED lights at the optimal color wavelength bathe greenhouse plants in light all day and most of the night. The result is highly productive crops. Compared with a wheat plant in the field that seeds once annually, a plant under 22-hour light goes through as many as six generations in a year, and at a sliver of the energy cost of yesterday’s heat lamps.

Mammals that forgo sleep risk illness or worse—but despite the growth demanded of the plants, “they’re healthy and productive,” says Lee Hickey, a seed biologist with the Queensland Alliance for Agriculture and Food Innovation in Australia. Trends toward urban farming and crop efficiency may open the method to other edible crops, such as corn and rice. And gene testing on productive crops will yield new answers for faster, less intensive, and more efficient growth—under lights or in the farmer’s field.