Those of us who live in the Seattle area can tell when fall arrives. The date depends not only on the vagaries of our climate cycles, such as El Nino but also on the given property’s microclimates and proximity to the Sound or to the mountains. Even though it may still be sunny there is a distinct nip in the air, usually sometime in September. It foretells months of shortened days and the rain, wind, and snow ahead. It is easy to be discouraged and want to batten down the hatches till spring. However, autumn is a season full of promise in the garden. Fall is the ideal time to plant all kinds of things from ornamental grasses and perennials to evergreen and deciduous trees and shrubs. Of course, plants of borderline hardiness should not be planted in autumn. Fall begins about 6 weeks before the first hard frost-that averages mid-November in Seattle. So, our window for fall planting is during September and October. Why is fall planting so good for plants? Cool, misty days are perfect for planting any time of year as they reduce transplant shock. The return of the rain is particularly auspicious for planting evergreens, trees and shrubs which may fail to thrive when planted in summer heat and drought. However, in the PNW, all hardy plants benefit from planting in the fall. It is a rare autumn indeed where we would need to give supplemental water in Seattle once the rain starts. In addition, the warm soil of fall encourages root growth. It’s estimated that 80% of root growth occurs in the late summer and fall. Roots continue to grow through the winter until the ground freezes. In early spring, roots continue to develop before top growth begins. While the fall-planted specimens are already becoming well established, the same size and variety planted in spring gets a slow start due to cool soils and lags behind in development. When summer finally arrives, the plant installed in autumn is far better equipped to deal with our dry Mediterranean summer, largely due to its well established root system. There are other good reasons to plant in the fall. The cooler weather tends to reduce pest and disease problems. Also, it is an excellent idea to buy plants in their season of highest interest. Quality and intensity of fall color may vary even within a particular variety, so when you buy during the season you can ensure that you get the color you want. Many plants are on sale at nurseries. Selection is reduced but sometimes the discounts reach 60-70% off the original price. Autumn is the perfect time to assess your garden. Decide what worked well this year and what didn’t. Does your garden give you beauty to look at in the fall? Just a few plants with gaudy autumn finery can make it spectacular. Now is the perfect time to improve your fall garden. Next year you will be glad you did!