Touring older neighbors is pretty free. drive around on a Saturday and check of the older part of town. Chances are good some folks with have some gardens that look good...and if they do look good the home owner may be out doing some gardening ...stop by and say hello they may want share some of their secrets.
I think she wants to know what was historically planted or displayed in the 1930's, not what people have planted around 1930's houses today. Very good question - no idea how you find this out, but landscaping/gardening preferences definitely change through the decades. I would suggest historical society.
Thank you for the tips! :) I grew up in NED ('76-'83 ) !! I miss it.
I've also checked the Smithsonian website, and it is AWESOME!!, it just takes ages (and I mean a loooong time) to find anything. I live in a historical part of our city now, but it's turn of the century, and there are a lot more resources/pictures.
You can find some pointers from the Historic Chicago Bungalow Association here:
I have a 1920's bungalow. Google "landscape craftsman home" or "landscape Bungalow" or search with "traditional" in front of the other words and you will come up with many resources including http://michaelweishan.com/gardenblog/?p=307 http://www.craftsmanperspective.com/advice/exterior.html http://www.ehow.com/info_8392976_traditional-bungalow-landscaping.html