Even though I have been gardening for about twelve years or so, I still consider myself a novice. I am always learning and adapting to new techniques and advice. The best advice that I have ever received was from one of my best friends and she helped me pick some great perennials. Her advice was to get perennials that self seed and self propagate; the reasoning behind her advice was based on several factors: economy, growth and sustainability.
I have many plants in my garden that you have seen through the course of my many picture sharings and so you have seen specimens of my dear friends great advice.
The best plants to fill up your garden with are the tall phlox, the cone flowers in all of their colors, hostas and lilies. You can divide them up without worrying about hurting them because they are very hardy and on their own they will do you the favor of multiplying all by their lonesome.