The American south is known for gardens. They have pretty good food quality if they want it. Many of them do not cook very good food, but they have plenty of ability to get it if they want. Which is to say for some reason more in the South do not value food quality, but for those who do they get it.
Neither food deserts nor rates of food insecurity have anything to do with food quality for those who want and can afford healthy food.
(I would have thought that California has the best food quality in the US because that is where most of the organic fruits and vegetables in the US are grown and the other elements of a healthy diet can be shipped around the world with very little loss of quality.)
