NASA's astronauts have had difficulty growing the plants, including a documented case of mold and over-drying around Christmastime. Kelly took the helm of the Veggie program and shared several tweets about its progress. At one point, he even said that they may need the help of Matt Damon's fictional character from The Martian. Just last week, Kelly tweeted that the flowers were "on the rebound." Now, the flowers have finally started to bloom.