I recently asked my Girl Scouts, what they would like to grow if they were astronauts based on a lunar outpost for an extended period time. I gave the girls four criteria for selecting their lunar garden crops:
- The first criterion was to choose a plant that was edible because although plants are great resources for changing CO2 into oxygen and transpiring water, astronauts based on the moon will desperately need plant-based food options.
- The second criterion required that the plant have some nutritional value—the more the better, but even iceberg lettuce has vitamin A and C. So, they had to consider the nutrient value of the plant.
- The third criterion was to try to pick a plant that grows relatively quickly. Astronauts on a Moon or Mars outpost don’t want to wait too long for a crop to be ready to harvest and eat.
- The final criterion was that the girls choose a plant that was appealing to them. It wouldn’t help to grow plants that met each of the first three criteria, but the girls would never want to eat that plant.
The four plants that the girls chose were watermelon, pumpkin, potato, and kale.
We’re growing these four plants in two different substrates. The treatment group is grown in a mix with 50% lunar regolith, 25% potting soil, and 25% vermiculite. The control group substrate is 50% potting soil and 50% vermiculite. At week four, the pumpkin plants are outperforming the three other crops in both the treatment and control groups. This is unexpected but makes the girls very happy.
