Plants In Space: How And Why Astronauts Grow Plants on the ISS

It has been nearly half a century since plants have been a part of the space program. On earth, with the growing world population, increasing incomes, and urbanization, the dependency on plants for basic needs is escalating at a faster rate. Similarly, in space, this reliance matters as due to a lack of Vitamin C (plant-based food), astronauts get scurvy, a disease caused by a serious deficiency of Vitamin C.  

As humans explore deep space, NASA considered it vital to take plants above for both aesthetic and practical reasons. Simply packing some multivitamins will not be enough to keep astronauts healthy. They will need fresh produce. So, it was noted that fresh flowers and gardens on the International Space Station (ISS) could create a beautiful atmosphere and supply the required fresh products. Moreover, plants can metabolize carbon dioxide in the air to produce valuable oxygen and can help control cabin humidity. They also will be critical for keeping astronauts healthy on long-duration missions.

Plant Habitats of NASA

Veggie

• Veggie, also known as the Vegetable Production System is a space garden that is situated in the International Space Station. Its major objective is to help NASA study plant growth in microgravity while adding fresh food to the astronauts and enhancing happiness and well-being on the orbiting laboratory

• Every veggie garden typically holds six plants. Each plant grows in a “pillow” that is filled with a clay-based growth media and fertilizer. The pillows are important to help distribute water, nutrients, and air in a healthy balanced manner around the roots, otherwise, the roots would either drown in water or be engulfed by air because fluids in space tend to form bubbles in space. LEDs are placed above the plants which produces a spectrum of light suited for the plants’ growth

• VEG-01, Veggie’s first crop in space astronaut Steve Swanson started the first crop of lettuce on May 8, 2014, which grew for 33 days. The first crop of lettuce had one pillow with no germination and two plants that were lost due to water stress. Three healthy lettuce plants were harvested after 33 days, frozen, and returned to NASA’s Kennedy Space Center for food safety analysis. Results were good with the plants being as clean.

Advanced Plant Habitat (APH)

• The Advanced Plant Habitat (APH)is a more sophisticated growth chamber. It is present on the ISS for plant research. It uses LED lights and a porous clay surface with controlled-release fertilizer to deliver water, nutrients, and oxygen to the plant roots

• But unlike Veggie, it is enclosed and automated with cameras and more than 180 sensors that are in continuous contact with a team at NASA’s Kennedy Space Center, because of which it doesn’t need much day-to-day care from the crew. Its water recovery and distribution, atmosphere content, moisture levels, and temperature are all automated

• When a harvest is ready for research purposes, the crew collects samples from the plants, freezes or chemically fixes them in such a manner that it can be preserved, and sends them back down to Earth so that scientists can better understand how space affected their growth and development.

Biological Research in Canisters (BRIC)

• The Biological Research in Canisters (BRIC) is a facility that is used to study the effects of space on organisms, such as yeast and microbes. BRIC-LED is the latest version that has been introduced, which (LEDs) to support biologies such as plants, mosses, cyanobacteria, and algae that need light to make their food

• In the BRIC-LED experiment, tiny plants are grown for 10 days, and then scientists spray them with flag-22 (set of 22 amino acids). An hour later, the plants are fully defending themselves, and scientists drench them with a chemical fixative to stop all biological processes

• This fixative does a great job of preserving the plants’ response state. They are later put into a deep freeze. The plants are later sent back down to Earth and then the first step is to have their Ribonucleic Acid (RNA) extracted and analyzed.

Plants Grown in Space

• Arabidopsis

• Bok Choy

• Rice

• Tulips

• Lettuce

• Cinnamon

• Sunflower

• Cabbage

• Kalanchoe

• Flax

• Parsley

Researchers are also examining the psychological benefits that astronauts can get by seeing, smelling, and caring for plants in isolated, closed-loop environments. Growing plants in space may also benefit humans on Earth by demonstrating the feasibility of using existing plant varieties in controlled environment agriculture.