If you live in LA you'll need to go over at least one highway.
Edit: ITT many Americans telling me of how walkable and great their towns are. I'm happy for you but comrades, I've been to the US once and that was on a trip I won in high school so don't expect me to know the zoning plan of Providence, Wisconsin Pop. 235'489. I don't really care how lovely your city with two buslines is. For every Seattle or Chicago there are 34 Cincinnatis, Houstons and Las Vagases and approx. 234 exurbs and suburbs.
the federal projects in my city, one of the only apartments that will rent to black people, is on the other side of the port and up a mountain, and the only way to get from that mountain into town is to drive across a bridge over the port that goes open air -> concrete wall -> the mirror of a car -> the other mirror of that car -> concrete wall -> the mirror of a car -> the other mirror of that car -> concrete wall -> open air.
The only things on that mountain aside from housing are, a gas station that doesn't sell gas, and a liquor store. I have a friend who lives there (bc shes black) & bc she has no generational wealth to provide for her a free car, it means she has to live off of gas station food every day of her life and has exactly 0 work prospects bc there's no bus that goes there even tho it's probably the highest concentration of people in the city. She is, effectively, in an open-air prison for poor people. My state is still openly segregated and has a ghetto that when you squint looks suspiciously like a concentration camp for minorities & poors
edit: its also the largest city in my state.
Are there spaces for market gardens available? Who owns them, and how would they react if their land was used?
what? no, its a complex squeezed onto a mountain abutted up against a military base & even if they did open one it'd probably get burned to the ground by the cops
That's a shame. How about roof top gardens?
its 100% built out, crammed between a base & a port, on the side of a mountain there are no empty lots