The MDRS’ GreenHab is an extremely lush, green place. Filled with large amounts of tomato plants, as well as many other plants in smaller amounts, it is an oasis of life in the middle of the Martian desert. The tomatoes have been yielding generously – currently over a hundred cherry tomatoes are on the path of ripening, soon to be ready to be enjoyed by the crew, and other vegetables and leafy greens are growing well. However, all the plants are growing in soil, a medium that has had to be brought over from earth at large expenses. Our two botanists, Frederic and Mario, are both working on improving the disadvantages that come from soil as a medium for growth. On the one hand, Frederic is focusing on growing plants in Martian regolith (the dusty, iron-rich sands that make up most of Mars’ surface and give it its red colour). His research focuses on the advantages of different types of regolith, mixed in various amounts, with or without HydroGel. HydroGel is a man-made substance, an acrylate polymer, which has the incredible propriety of being able to absorb over 100 times its own weight in water, and release it slowly. This is extremely useful in dry climates back on Earth, as well as on Mars, where water is extremely precious.
On the other hand, Mario is working on a project that is somewhat the opposite : a hydroponics system. In such a system, plants are growing without soil, or any nutritive medium. Instead, their roots are hanging in a recirculated flow of nutrient-rich water, feeding them without wasting any water. In such a system, the nutrient composition of the water, as well as its pH and other factors, can be controlled with great precision to suit the plants. In addition to this, no water is wasted since it is recirculated, and the vertical format of the towers allows for minimal waste of space, also a precious resource in an extra-terrestrial station.
Both experiments are well underway! Fred has finished planting all his seeds and is waiting for them to sprout to start taking measures, whereas Mario has finished building the last of his three towers today.
All other experiments are also well underway ! Time is passing fast, and we are soon approaching the middle of our stay in the MDRS, even though we feel like we just got here. On Sunday, as a middle mark of our stay, we are planning a break day in our experiments, and a small celebration (with more cake!). In the meanwhile, we’ll keep on working hard, as there is no shortage of things to do here on Mars.