Skip to main content

Astronauts on the ISS pick a second peck of chili peppers

Astronauts on board the International Space Station (ISS) have harvested a second batch of chili peppers grown on the station, bringing to an end one of the most complex experiments in growing plants in space to date.

Although some edible plants have been grown on the ISS before, like leafy greens and radishes, the experiment with chili peppers was more challenging than the previous experiments because the chilies are flowering crops and grew for a total of 137 days, compared to the one or two months most previous plants had been grown for.

The four pepper plants that grew for 137 days aboard the International Space Station are pictured shortly before the second and final harvest for the Plant Habitat-04 experiment.
The four pepper plants that grew for 137 days aboard the International Space Station are pictured shortly before the second and final harvest for the Plant Habitat-04 experiment. NASA

The chilies were grown in the ISS’s Advanced Planet Habitat as part of an experiment called Plant Habitat-04. “PH-04 pushed the state-of-the-art in space crop production significantly,” said Matt Romeyn, principal investigator for PH-04 from NASA’s Kennedy Space Center in Florida. “With this experiment, we took a field cultivar of a Hatch chile pepper from New Mexico, dwarfed it to fit inside the plant habitat, and figured out how to productively grow the first generally recognized fruiting crop in space – all in a span of a couple of years.”

The first batch of chili peppers was harvested on October 29 and was turned into tasty tacos for the crew. One of the big advantages of growing chilies is that their spicy flavor is appealing to astronauts, who often request condiments like hot sauce to make their food more interesting.

“The level of excitement around the first harvest and the space tacos was unprecedented for us,” Romeyn said. “All indications are some of the fruit were on the spicier side, which is not unexpected, given the unknown effect microgravity could have on the capsaicin levels of peppers.”

As well as the physical health benefits of fresh vegetables, tending to crops and then harvesting and eating them can be psychologically beneficial for the astronauts as well.

“The biggest benefit that I’ve seen personally is the impact growing plants has on the crew,” said Nicole Dufour, PH-04’s project manager. “They are so engaged when they are interacting with the plants, especially when it’s a crop plant like the peppers. We discovered the crew had been taking the door shade off every day to check on the plants and look at the peppers. That’s not something we asked them to do – they just wanted to because they enjoyed it so much.”

Editors' Recommendations