To be frank, I am not interested in clients who want to hire me to fix their punctuation. As a writer, it is your job to learn the tools of your trade. This is basic stuff that we all learn in grade school. The strongest writing I see is from people who also have a good grasp on punctuation. It seems to go hand in hand. But even if it doesn't, it just takes a little effort to learn the rules and make your writing stronger and clearer.

Passing the buck to an editor will never make you a stronger writer. Your analogy breaks down in light of the fact that the most dedicated gardeners do their own weeding.