I remember "colony gardens" from growing up in Copenhagen in Denmark. It was a great way for people living in apartments to get outside. Most had very elaborate shed/tiny house structures, and you were actually allowed to live there over a certain number of weekends during the late spring to early fall.

I learned a lot about gardening in a tiny space from visiting my maternal grandparents at their plot, with their little 250sq foot house. Good memories!

Glad they are becoming more popular in the US!