Science in bloom
2016-01-19
On Jan. 15, Scott Kelly tweeted a picture of the first flower grown in the Veggie plant growth facility aboard the International Space Station (ISS). Like many activities on the orbiting laboratory, growing flowering plants is more complicated than on Earth, while at the same time yielding a wealth of research data that is vital to long-duration missions.
The zinnia flowers had a rough start. They began exhibiting signs of stress consistent with too much water and not enough air flow around the roots. Plans were made to increase the root ventilation, but they had to wait until after the unplanned spacewalk on Dec. 21.
By Dec. 24, however, the opposite problem appeared. The zinnia plants were now exhibiting signs of drought stress, but the next scheduled watering wasn’t for three more days. Kelly worked with the Veggie team and, ultimately, became responsible for the care of the zinnias, with the Veggie team providing a single sheet of guidelines rather than detailed procedures.
The zinnias follow the red leaf lettuce that was successfully grown and harvested last year aboard space station. They were chosen because they can help scientists understand how plants flower and grow in microgravity.
“The zinnia plant is very different from lettuce,” said Trent Smith, Veggie program manager. “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.”
The zinnia flowers had a rough start. They began exhibiting signs of stress consistent with too much water and not enough air flow around the roots. Plans were made to increase the root ventilation, but they had to wait until after the unplanned spacewalk on Dec. 21.
The discovery of mold on some of the zinnia leaves on Dec. 22 was serious enough to get the Veggie team out of bed at 4 a.m. to send new procedures to Kelly. The affected leaves were removed and frozen for later study, while the remaining leaves and plants were cleaned and disinfected. The fans were set to high to dry out the chamber and combat the high humidity and mold growth.
The zinnias follow the red leaf lettuce that was successfully grown and harvested last year aboard space station. They were chosen because they can help scientists understand how plants flower and grow in microgravity.
“The zinnia plant is very different from lettuce,” said Trent Smith, Veggie program manager. “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.”
For more information about the Veggie project and the trials and tribulations of space gardening, visit the ISS website.
Zinnia in bloom. First flower grown in the Veggie plant growth facility on the International Space Station. Image Credit: NASA
Michelle Fraser-Page
NASA Johnson Space Center
Zinnia in bloom. First flower grown in the Veggie plant growth facility on the International Space Station. Image Credit: NASAMichelle Fraser-Page
NASA Johnson Space Center
Zinnia plants on ISS show signs of stress. Image Credit: NASA
Zinnia plants showing improved health on ISS. Image Credit: NASA