RSync Command Question

I am looking to use rsync to sync two directories. I am doing a test with two folders. Folder 1 and Folder 2.

I want folder 2 to looks like folder 1. Folder one has 1 folder and one file, folder 2 has a folder not located in folder 1.

I use:

rsync -a -delete ~/desktop/'folder 1' ~/desktop/'folder 2'

The items from folder 1 move to folder 2 but the extra directory is not being deleted. What am I missing?

Thanks

mi