I have come to appreciate the natural style of gardening as an expression of how our plants interact with the weather, climate, and in the growing conditions where I live. As much as I used to enjoy gardens with large numbers of different plants and more structured, detailed designs, I have come to greatly appreciate a garden where many of the plants have, over time, spread and established themselves in new places, by propagating themselves through re-seeding. These "volunteers" (re-seeded children of the original plants) are survivors that have found places that are well suited to their needs. Consequently, they need very little care to look their best.
Some of my favorite, non-weedy naturalizing perennials: