While NASA is growing plants in space, they aren’t the flesh-eating variety, at least not this time. Lettuce was the first plant successfully grown and consumed on the International Space Station (ISS). Salad is a welcome alternative to freeze dried, pre-packaged space food, but what is a salad without tomatoes? As a precursor to growing tomato plants on the ISS, scientists are growing zinnias in the onboard Vegetable Production System (VEGGIE); and the plants have went through numerous trials since the experiment started in mid-November.
It hasn’t been all sunshine and roses with the zinnia experiment. Originally, the VEGGIE module was programmed with a strict schedule of watering and air flow that was predetermined and completely automated. Conditions took a downward turn when the zinnia leaves started curling in late December, indicating that the plants were getting too much moisture. This was relayed to the ground team, who in turn decided to turn the fan up to a higher speed. The fix was delayed and the excess moisture eventually caused mold on some of the plants. Astronaut Scott Kelly soon became the onboard gardener, donning a dust mask, he surgically removed the moldy leaves from the plants and preserved them for later study. The fan speed was then turned up to help dry out the plants and prevent future mold issues. However, the increased wind speeds worked a little too well and started drying out the plants.
Scott Kelly came to the rescue of the VEGGIE team and suggested that the gardening be handled by the astronauts onboard. Applying traditional gardening techniques like, ‘Hey, this plant looks thirsty let’s water it’, to the high-tech VEGGIE module serves two purposes: the astronauts can respond to plant conditions in real-time as well as mimic the conditions of future space travel, where the astronauts will be responsible for plant growth. Armed with the newfangled “Zinna Care Guide for the On-Orbit Gardner,” Scott Kelly took over the day-to-day care of the zinnia plants. Within a few weeks, the two remaining plants looked healthier than ever and produced blooms. This rollercoaster experiment with plant growth in-orbit has produced insightful results that will continue to inform researchers as they diversify the onboard vegetation. Next up is Chinese cabbage and red romaine lettuce, and in 2018 they hope to send up dwarf tomato seeds.
Fresh food will be a welcome alternative for astronauts stuck in space for long periods of time. As well as providing much needed nutrients, plants also serve a psychological purpose, helping to connect people to Earth when surrounded by so much space and automation. A little reminder of home and splash of color in a monotonous, claustrophobic environment.