[frankus]

I like to say that the best thing you can grow in your backyard from an environmental and financial perspective is an ADU ("granny flat"). At least assuming you live closer than average to a job center.

The second best thing would be herbs (since they cost a fortune at the store and are only available in quantities that will spoil before they're used up).

The third best thing, as the article says, are things that are costly to produce on a farm but grow like well with little maintenance in small spaces (my favorite here in the Salish Seaboard is raspberries).

The fact is that "people miles" are astronomically more costly than "food miles" or almost any other kind of miles. People are impatient, fragile, don't like to be stacked, prefer a relatively limited range of temperatures, and their loved ones usually consider them irreplaceable. Just about any other type of cargo is easier to deal with.

I do see a niche for growing stuff in places where the light, water/humidity, and heating/cooling needed to grow plants is already being produced for humans sharing the space. Basically an amenity that happens to produce food, which in a lot of cases would include the gardens discussed in the article.