NASA’s VEG-01 program is going pretty well so far. Last year, they successfully grew lettuce in space using the new LED-greenhouse aboard the International Space Station. On Sunday, astronaut Scott Kelly posted a photo of a zinnia in bloom, part of the same project to see what can be grown under artificial light in zero gravity.
The plants weren’t doing so well around Christmas, with Kelly tweeting photos of mold growing on leaves. But even what looks like a failure is important in science, because it provides NASA experts back home with information on what not to do when gardening in space.
According to Trent Smith, the project manager for “Veggie,” the zinnias weren’t chosen for beauty’s sake. They were selected specifically because they’re difficult to work with:
“The zinnia plant is very different from lettuce… It is more sensitive to environmental parameters and light characteristics. It has a longer growth duration between 60 and 80 days. Thus, it is a more difficult plant to grow, and allowing it to flower, along with the longer growth duration, makes it a good precursor to a tomato plant.”
Two weeks into the growth cycle for the zinnias, astronauts noticed water leaking from the greenhouse. Soon the plants were showing signs of root flooding, and the humidity was too high in the growing space. This led to the mold problem, which was why Smith got a phone call at three in the morning. A team was formed in the wee hours to figure out what to do.
They eventually let Kelly take over caring for the plants himself. He fixed the fan speed so it wasn’t too humid, and watered the plants when they needed it (instead of according to a fixed schedule determined on the ground). The moldy leaves were clipped away, freeze-dried, and stored for testing. By the weekend, the remaining plants were in bloom.
It’s definitely a nice sight to see not only for the astronauts, but everyone back home. Now if they can just hurry up with the Mars potato project, we can start colonizing the rest of outer space.