Scientists grow plants in soil from the moon for the first time

On July 20, 1969, American astronaut Neil Armstrong became the first human to step on the moon. He made the historic lunar event together with fellow astronaut Edwin “Buzz” Aldrin after they landed on the moon in the Lunar Module.

They walked around for three hours while Michael Collins, the third astronaut of Apollo 11, stayed in orbit around the moon.

During their three-hour stay on the moon, the two astronauts did some experiments. They put up the US flag and a sign on the moon and took 21.6 kilograms of geologic materials, including two core samples, rocks and lunar soil, also known as “regolith.”

Another historic first—more than 50 years later

On May 12, 2022, three scientists from the University of Florida (UF) revealed through a news release a breakthrough discovery that took decades in the making—they have successfully grown plants in lunar soil.

For the first time in human history, scientists marked a milestone in lunar and space exploration when they showed that plants could successfully sprout and grow in lunar soil.

UF Scientists Anna-Lisa Paul and Robert Ferl are internationally recognized experts in studying plants in space.

For 11 years, Paul and Ferl applied three times for a chance to work on the lunar regolith, which NASA has kept unopened and pristine for 50 years.

NASA approved their application and loaned the scientists 12 grams of lunar soil collected during the Apollo 11, 12 and 17 missions for their research.

Ferl, a professor in the Horticultural Sciences department at UF, said, “We first asked the question of whether plants can grow in regolith. And second, how might that one day help humans have an extended stay on the Moon.” The answer to the first question was a resounding “yes.” Plants can grow in the lunar regolith.

Model plant + small samples = great results

For their experiment, the UF research team used Arabidopsis thaliana, also known as thale cress, a popular model plant among scientists due to its small size and ease of growth.

Arabidopsis is native to Eurasia and Africa and is a relative of mustard greens, broccoli, cauliflower and Brussels sprouts. It is one of the most studied plants in the world, and its genetic code has been fully mapped in 2000.

Scientists already know what its genes look like, how it behaves in different circumstances, and even how it grows in space.

According to the news release, to grow Arabidopsis in just a few teaspoons of lunar regolith, Paul and Ferl used a simple experiment: plant seeds in lunar soil, add water, nutrients, and light, and record the results.

To grow their tiny lunar garden, the research team used thimble-sized pots in plastic plates. Each pot had approximately 1 gram of lunar soil moistened with a nutrient solution and planted with a few Arabidopsis seeds.

For comparison, the researchers also planted Arabidopsis seeds in a terrestrial substance called JSC-1A, which mimics real lunar soil. The plants grown in JSC-1A were the control group of this experiment.

Before the experiment, the researchers were unsure if the Arabidopsis seeds planted in the lunar regolith would sprout—but nearly all of them did.

“We were amazed. We did not predict that. That told us that the lunar soils didn’t interrupt the hormones and signals involved in plant germination,” Paul said.

The UF and NASA news releases described the experiment in full detail.

The Arabidopsis seeds sprouted two days after they were planted. Six days later, however, the researchers observed that the plants were not as robust as the ones in the control group.

The researchers observed differences between the plants grown in the lunar soil and the control group. Some of the plants grown in the lunar soils were smaller, grew more slowly, and have more varied sizes than their counterparts in the control group.

The plants in the lunar soil had stunted roots and leaves and showed reddish pigmentation.

According to Paul, these signs show that the plants were coping with the chemical and structural make-up of the lunar soil.

Their observation was later confirmed when the researchers analyzed the plants’ gene expression patterns.

Working with Stephen Elardo, an assistant professor of geology at UF, Paul and Ferl said that the plants’ response to lunar soil may be linked to where the soil was collected.

The researchers found that the plants that showed signs of stress were grown in mature lunar soil that was exposed to cosmic wind. On the other hand, plants grown in comparatively less mature soils fared better.

Day 16 after the Arabidopsis sprouted, show clear physical differences between plants grown in the control medium (left), compared with those grown in the lunar soil.

Twenty days after sprouting, before the Arabidopsis plants started to flower, the team harvested the plants and mapped their RNA.

The RNA sequence revealed that the plants were stressed, and reacted in a way that researchers have previously seen  Arabidopsis respond to in harsh environments.

First steps toward growing plants on the moon

This scientific breakthrough comes at a time when NASA’s Artemis Program is set to send the next astronaut to the moon.

Jacob Bleacher, the chief exploration scientist of NASA’s Artemis program, points out that while they send robotic missions to the moon’s South Pole to explore the presence of water that can be used by future astronauts, they will also study how plants can grow on the moon.

As scientists explore the potential of growing plants on the moon in the future, additional questions must be answered, more studies and research are needed, and more missions will be sent to the moon. While we wait for these answers, let us join the researchers in celebrating the first steps toward growing plants on the moon.

Clement  Dionglay is with ISAAA Inc.’s Global Knowledge Center on Crop Biotechnology.

Image credits: UF/IFAS photos by Tyler Jones