Astrobiology students cultivated leafy greens, sweet potatoes, and even hops in simulated Martian dirt.

NASA and private entrepreneurs are pushing to land people on Mars within the next generation. To survive on Mars, colonists will need a lot of gear, not least of which is food. Since lugging food adds a lot of weight to spacecraft — and packaged food only retains its nutrients for so long, anyway — any would-be Martians will need to grow food on site in order to survive.

But conditions on the Red Planet are different than on Earth. The surface receives less than half the amount of sunlight that Earth does, and dust in the atmosphere can attenuate it even more. Due to the absence of an ozone layer, more ultraviolet radiation reaches the ground. As to the Martian surface itself, the dirt (technically “regolith”) is more iron-rich, particularly in iron oxides.