Before we can cultivate plots of Martian potatoes (as Matt Damon’s character does is in a certain space flick out this week), we’ll need to know a lot more about how plants grow in extreme climates. Enter Anna-Lisa Paul and Robert J. Ferl of the University of Florida’s Space Plants Lab in Gainesville. This week on The Macroscope, video producer Emily Driscoll explains how Paul and Ferl sent a lowly weed—affectionately called “crackwort”—to the International Space Station to study how the plants’ roots grew in zero gravity.

Plus, NASA astronaut and avid space gardener Don Pettit joins Ira and Emily to talk about his quest while aboard the International Space Station to grow “the space equivalent of the potted plant in the corner of the office.”

To hear a radio adaptation of Don’s “Diary of a Space Zucchini” blog, click here.