I wonder if the Earths microbiome is offering some assistance here. <br>Obviously on Mars plants would be exposed to the microbiome we carry around in and upon us, but there is a lot more just hanging around just about everywhere on Earth, so would that make a substantial difference? and could it be eliminated as a factor, in a budget experiment like this? (Sterilizing the soil seems like itd be easy enough, but Im not sure about the other details.),(reply>), Really good point! This video was really my attempt to introduce people to the fact that real researchers are putting in real time and effort into discovering how to grow crops best on Mars. Their conditions are much more controlled for the variables that you spoke about, and they use different mixtures of fertlisers etc. (I just used standard garden centre fertiliser)!