Can you start a botanical garden on the moon? Yes, scientists appear

But your crops might get a little stressed…

NASA plans to return to the Moon in this decade. And this time forever. Because the intent is that the moon will eventually be inhabited by astronauts. This means that they must also be able to grow their own food. The burning question is of course how. Because… is lunar soil really suitable for this?

washed over the moon
The idea is that the moon will eventually be used as a springboard for longer space missions in the future – such as Mars. “It makes sense, then, to grow crops on land that already exists,” explains researcher Rob Ferrell. “But what happens when you grow plants on lunar soil, something outside the plant’s evolutionary experience? In short, what do plants do in the lunar greenhouse? Could we have lunar growers in the future?”

Experiment – Experiment
To answer all of these questions, researchers in a new study designed a deceptively simple experiment: plant seeds in lunar soil, add water, nutrients, and light, and record the results.

problem
The problem: The scientists only had 12 grams—just a few teaspoons—of lunar soil to perform this experiment. This soil was collected during Apollo 11, 12, and 17. This small amount of lunar soil, not to mention its invaluable historical and scientific importance, meant that researchers had to design a small, carefully designed experiment. To grow a small “moon vegetable garden,” the researchers used thimble-sized wells in plastic dishes typically used in cell culture. Each works well as a container for culture. After filling each “pot” with about a gram of lunar soil, the scientists moistened the soil with a nutrient solution and added some Arabidopsis seeds.

Why Arabidopsis?
Arabidopsis is widely used in botany because its genetic code has been fully mapped. Growing Arabidopsis in lunar soil gave the researchers more insight into the soil’s effect on plants, right down to the level of gene expression.

Prior to the experiment, researchers were not sure that seeds planted in lunar soil would germinate. But the team made a surprising discovery: almost all the seeds had sprouted, a first in human history and a milestone in lunar and space exploration.

sprout
“We were very surprised,” researcher Anna Lisa Poole recalls. We did not expect this. Hence it indicates that the lunar soil apparently does not interrupt the hormones and signals that go into plant germination.”

Can we start a botanical garden on the moon? Yes, although some caution is advised. Despite the seedlings germinating, the team noticed significant differences between plants grown on lunar soil and volcanic ash. For example, some plants growing on lunar soil were smaller, grew more slowly, and were more varied in size than their terrestrial counterparts. ‘Moon plants’ took longer to develop expanded leaves and often had stunted roots.

Stress
In short, moon plants showed more signs of stress. “We can conclude that the plants suffer from lunar soil fatigue,” Paul says. However, we must not lose hope now. “Ultimately, we want to use the gene expression data to explore how we can improve stress responses,” the researcher continues. Then we can then grow plants – especially crops – on lunar soil without affecting their health. “

the bottom of the moon
How plants respond to lunar soil may also be related to where exactly the soil was collected. For example, the researchers found that the plants grown in the Apollo 11 samples did not grow as well as the plants in the Apollo 12 and 17 samples. However, the researchers have a definitive explanation for this. For example, plants that showed the most signs of stress seemed to have grown in soil more exposed to cosmic winds, which altered their composition. The presence of small particles of iron in the soil can also cause additional stress to plants and stunt their growth.

vice versa
Conversely, researchers believe that plant growth may in turn alter the moon’s soil. Although the specific mechanisms are not yet known. “The moon is a very dry place,” said researcher Stephen Elardo. How will the minerals in lunar soil react when a plant grows on it, adding water and nutrients? Will adding water make mineralogy more suitable for plants? “

Follow-up research will build on these questions and more. But for now, scientists are celebrating taking the first steps to growing plants on the Moon. “We wanted to do this experiment because we always wondered if crops could grow on lunar soil,” Ferlo says. “The answer, as it turns out, is yes.”