So, here's my situation: my first book revolves around an unknown entity giving modern day humanity an assortment of supernatural powers. Every week a new power is given to everyone on Earth over the age of 13, and they can hold up to 6 at a time. Once they hit 6, they choose which of the ones they have will be replaced by the next week's power. In addition, everyone has a few permanent powers that don't count towards this 6 power limit and cannot be removed.
By the end of the first book, a full year of humans getting powers society can't handle humans having, combined with a few powers seemingly intentionally designed to destroy the world's infrastructure, have knocked the world down to the tech level of your average zombie apocalypse. The entire world's infrastructure (power lines, phone lines, internet, water treatment, etc) is now in ruins due to a previous power, and any attempt to fix it is pointless because now one of the permanent powers that everyone over the age of 13 has is the ability to temporarily disable any technology they want to as long as it's in their line of sight. Which also means that they can't even rely on most modern means of transportation. For more information on how this anti-technology power works, see here. But stated simply, people can still use modern technology if they can get the fuel or electricity to power them, but if anyone who's looking at it wants to, they can temporarily make it useless with just a thought.
That's the bad news. The good news is that everyone over the age of 13, male and female, has the strength of two men, is four times as durable, is immune to disease and aging, and can heal from any injury that doesn't kill them in a week at the longest, all with no added calorie intake except for regrowing lost tissue (these are the permanent powers I mentioned earlier).
So here we come to the main issue: rather than the usual post-apocalyptic plot of the main characters making a pilgrimage to the ultra-rural countryside and hoping to find a place where they can grow food, I want the main character's small suburban hometown to turn into a sort of post-apocalyptic city-state run by a local billionaire who, for his own reasons, stockpiled the necessary supplies to make the town self-sufficient enough to feed and defend themselves.
Is that possible? Is there enough land in the average small suburban town that, if given the tools, seeds and other supplies, people with the powers described above could grow enough food to support the town's pre-collapse population? And if not, what is the fundamental obstacle they'd face which I'd need to create a power to compensate for?