Taking plants off-planet – how do they grow in zero gravity?

Header image: Astronaut Cady Coleman harvests one of our plants on Space Shuttle Columbia. NASA, CC BY

Gravity is a constant for all organisms on Earth. It acts on every aspect of our physiology, behavior and development – no matter what you are, you evolved in an environment where gravity roots us firmly to the ground.

But what happens if you’re removed from that familiar environment and placed into a situation outside your evolutionary experience? That’s exactly the question we ask every day of the plants we grow in our laboratory. They start out here in our earthbound lab, but they’re on their way to outer space. What could be a more novel environment for a plant than the zero-gravity conditions of spaceflight?

By studying how plants react to life in space, we can learn more about how they adapt to environmental changes. Not only are plants crucial to almost every facet of life on Earth; plants will be critical to our explorations of the universe. As we look to a future of possible space colonization, it’s vital to understand how plants will fare off planet before we rely on them within space outposts to recycle our air and water and supplement our food.

So even while we stay right here on the ground, our research plants blast off and head to the International Space Station (ISS). Already they’ve given us some surprises about growing in zero gravity – and shaken up some of our thinking about how plants grow on Earth.

Plants make especially great research subjects if you’re interested in environmental stress. Because they’re stuck in one spot – what we biologists call sessile organisms – plants must cleverly deal in place with whatever their environment throws at them. Moving to a more favorable spot isn’t an option, and