Excuse me for what might be a very silly question but I'm completely new to gardening. I have prepared a sloped part-shade garden bed that is about 30 X 40. I want to plant a few larger, flowering evergreens as a background plant at the very top of this slope. Can you buy large camellias that would be about 4' tall or even taller? I was thinking about rhododendrons but then came across camellias and they are just beautiful. If I want some larger plants across the top, I just didn't know if I could purchase camellias this size. Thanks for any thougths.