All they will need is some kind of health scare related to a mythical plant fungus, and the gardens will be gone - or raided by SWAT teams.
That’s right.
“...health scare related to a mythical plant fungus...”
No need to use a mythological one, the real ones are scary enough.
Arizona produces a lot of wheat, oddly enough, along with 47 other states. However, testing in two samples showed a fungus called “karnal bunt”, so the USDA ordered that all AZ wheat was to be destroyed, and no more could be planted or harvested for FIVE years.
The USDA does not do “saving” or “retesting”, only destruction. Lots of foreign products are banned on the off chance they have some pathogen in or on them. And they are still chasing all over the place trying to put out “wildfires” (see The Andromeda Strain), destructive insects, invasive plants and animals, etc.
It’s a losing game.