I have a 1 week old 26 gallon freshwater tank with gravel and several fake plants. Should I add real plants? What are the benefits? When should they be added? What would be some good plants to start with?
The short answer is YES, add plants! You and your fish will love it. You can add them immediately. They'll also prevent algae as time goes on, because they use up the nutrients that algae need. Plus they provide hiding places for your fishies.
The thread Fishiebusiness referred you to is very complete and useful. Try it--you'll never go back to plastic.