Episode 8.11
In a plot set-up trope that is becoming all-too-familiar, Alan crashes the Saucer into the Red Planet leaving him with no supplies and months to wait for rescue. With his usual stoicism, he announces at the start of the show that, in the face of overwhelming odds, he has only one option: to science the shit out of this.
The seeds happily found in his naval fluff, back then, have now germinated but not quite into the potatoes he needs in order not to starve to death. Still, in the meantime, they look quite pretty.