Zinnias are the second species of plant successfully grown on board the ISS.
The first flowers ever grown in space are blooming on the International Space Station. The flowers are zinnias, and they are considered a small step toward NASA’s goal of one day growing food for the space station and exploration missions of long duration.
Astronaut Scott Kelly tweeted an image of the flower over the weekend. They are the second species of plant successfully grown on board the ISS. Lettuce was planted in July and astronauts were able to harvest and even eat the fresh leafy greens. This was the second attempt at lettuce. The first batch failed due to drought stress, so they were “very vigilant with respect to the second crop,” according to Veggie project manager Trent Smith.
Smith says growing zinnias is very different from growing lettuce, as it is even more sensitive to its environment. It also has a longer growth duration of 60 to 80 days. He says these factors make it good practice for growing tomatoes, which will be the next crop.
The space flowers showed signs of stress early on, thought to possibly be due to high humidity or too much water. The excess moisture caused some of the leaves to become moldy.
Astronaut Kelly took over garden duties on the International Space Station from NASA astronaut Kjell Lindgren in December. He cut away the moldy plant tissue and sanitized the plant surfaces with cleaning wipes. Fans were operated at high speed to try and keep the Veggie chamber dryer. However, the fans dried out the plants too much. Kelly called earth on Christmas Eve to say they needed water, even though the next scheduled watering was on Dec. 27. He asked for the autonomy to decide on his own when to water the plants.
The ground gardeners turned over the gardening duties. Smith said Kelly “has the helm.” They just provided him some guidelines to understand zinnias.
Growing plants in space is in the public eye lately due to the Matt Damon movie The Martian. Damon’s character, who is left alone on Mars, survives by growing potatoes for food. The International Space Station’s lettuce and zinnias may be a first step toward making this scenario a reality. The world will be waiting to see if space tomatoes become a success.