Is Insect Waste the Key to Growing Plants on Mars?
01.07.2024 - 09:49
/ theunconventionalgardener.com
/ Emma Doughty
Header image credit: Texas A&M University Engineering
Emmanuel Mendoza, an aerospace engineering student at Texas A&M University, has been tackling one of humanity’s biggest challenges: how to survive on another planet. It all started with a science project – testing if radishes would grow in simulated Martian regolith – in his parent’s garage during his senior year of high school.
Now he’s using the Forensic Laboratory for Investigative Entomological Sciences (FLIES) Facility at Texas A&M to try growing pea plants in simulated Martian soil with the help of black soldier flies.
“I’ve always been interested in human space systems, specifically, how we grow or how humans live in long-term space environments,” said Mendoza. “Black soldier flies are on the rise due to their ability to break down basically any organic matter – faeces, animal waste, organic waste, plant matter – a lot of things that are generally non-useful.”
After digesting these waste materials, black soldier fly larvae produce frass – essentially insect poop.
“Because of the way their gut works, it is found to be a really good soil supplement, like fertilizer to plants,” said Mendoza. “I saw this and thought, if you can use this for plants, what’s to prevent you from using it with something that doesn’t usually support life?”
Mendoza’s experiments involving potting pea plants in regular soil and Martian regolith simulant, supplemented with varying amounts of frass, from zero to 100%.
To his surprise, he found that plants potted in plain Martian soil were able to flower and grow pods. Adding 10% frass to the Martian soil was the optimum amount for plant growth. More than 50% frass, however, and the plants failed.
“This tells us that frass is being used by the soil.