It's been raining the last few days, but before it started in earnest, I was able to build and fill this:
I topped this store-bought version off. If you look real close, you can see some of the stuff I already planted. (Ignore the junk and overgrown, soon-to-be-herbicided grass.)
The bonus? These rains proved my regrading project a success. The area where the walk meets the patio didn't get swamped at all.