These Bio-Hacked Petunias Change Color On Demand

Synthetic biology comes to your garden: Just water these petunias with some old beer, and the white flowers will turn dark pink. Impress your friends!

At first glance, Nikolai Braun’s petunias look like any other petunias. What makes them special is what happens when you start watering. They change color.


Braun heads Revolution Bioengineering, a Colorado based startup that is bringing the power of synthetic biology to everyday horticulture. And the possibilities are truly mind-blowing. Gardeners could begin to change plant colors on-demand, and grow plants that take on different hues depending on the time of day.

Take a look at the petunia in the video above. See how it changes color as it grows, going from a pale white to a darkish pink. The plant is deficient in a certain enzyme related to its pigmentation. It starts as a blank slate color-wise, before taking on color in response to a molecule that expresses that enzyme. You just need to water with a solution of ethanol (or even old beer).

Revolution Bioengineering was founded by Braun and his partner Keira Havens. The biologists worked together at Colorado State University where they collaborated on a Department of Defense-funded project to develop plants that could sense explosives.

“We’d always had an entrepreneurial bent and we wondered whether there was opportunity where we can make a difference, and where we can demystify this technology so it’s not so alien or foreign,” says Braun. “We came up with the idea of horticultural technology–beautiful, unique flowers for anyone to enjoy.”

The partners are now crowdfunding their first idea. For $42, you get you one plant; $89 gets you three. You’ll have to wait a while, though. Shipping is set for the spring of 2017 “at the earliest.”


Their second project, known as “Petunia Circadia,” is more ambitious still. It’s a flower that changes color throughout the day according to its circadian rhythm.

“There are natural timing switches within a plant, the best example of which is photosynthesis, where a plant gets energy from light,” Braun says. “It’s only necessary to have that machinery on during daylight hours [when the sun shines]. At night, the plant shuts all of that down. We can use that mechanism to change the color of the flower.”

That specimen doesn’t exist yet. But Braun says the science is well established, though he needs to find funding first. He hopes the first project will lead to the second.

Is manipulating flower colors a, well, useful invention? We have our doubts, though Braun makes a decent case. The flowers are advertising the wider possibilities of synthetic biology in the home, he says. Braun sees opportunities to produce alternative air fresheners where plants are engineered to produce certain popular smells, like, say, vanilla. (Ironically, other startups are working on the opposite problem: reproducing the scent of natural flowers using genetically engineered yeast.) Floral technologies could also be applied to commodity plants like cotton and cannabis.

“The horticultural industry is driven by novelty. Every year, they’ve got to come up with something new that knocks your socks off,” he says. “I appreciate flowers as much as anyone. But there’s always that need for improvement: more vigorousness, brighter colors, prettier flowers, and different forms we can appreciate.”


About the author

Ben Schiller is a New York staff writer for Fast Company. Previously, he edited a European management magazine and was a reporter in San Francisco, Prague, and Brussels.