Depending on how much you want your website to do, you don't necessarily need to know THAT much PHP. But it can certainly help especially if you're integrating several different plugins into your theme, for example.
I built
this website for a charity I volunteer with, using a pretty stock installation of WordPress 3, and a variety of useful plugins. It's still a work in progress (well, what site isn't?) but so far we are really liking what we can do with WP.
That camp website consists of:
- Stock WordPress 3 installation
-
Ashford CMS theme with a few modifications to the color scheme and my own banner graphic
- a bunch of static pages and a blog with several different categories
- a ZenPhoto gallery (separate from WordPress)
- a plugin for integrating the ZenPhoto gallery and pulling photos into WP pages/posts
- a Colorbox/Lightbox plugin for stylish display of images
- a plugin to pull events from Google Calendar and display them in a sidebar or on a page ("Events")
- a plugin for pulling lists of posts in a custom style for the front page news headlines
- a plugin for handling polls
- a plugin (work in progress) to allow visitor subscribers to receive weekly emails about site updates
There are other plugins as well but those are some of the more prominent ones. I have plans for more, such as a plugin to run a simple shopping cart to sell camp merchandise online. I didn't really do a whole lot of custom code writing in PHP other than perhaps restyle some existing output from some of these plugins.
In addition to these plugins the site benefits from WordPress's graphical editor which allows any of our volunteers to edit or add site content with a minimal knowledge of HTML.