There is quite a bit of ongoing discussion as to whether it is better to clean up deciduous plants in the fall or spring. I prefer fall, primarily because the fog is not kind to dying plant material. I would rather clean up and have less mold. Also, our spring comes so early, and enough plants grow all year, I think it helps both the looks of the garden, and the chance for self sown plants as well as perennials to get a good start come February.
One fall task that seems to be universally accepted is preparing the soil for spring growth. I do not dig beds, as there is enough evidence supporting just covering the ground with supplements rather than digging them in to appeal to my lazy side. Supposedly not digging also cuts down on weed seeds sprouting, which I can also totally support. However, the dirt needs feeding. The idea is that mulch put down in fall breaks down and the nutrients washed into the soil throughout the winter, regardless of climate. The cheapest mulch for this purpose is cow manure. So I am in the midst of spreading manure on all the beds. Then there are a few more plants to cut, including these asparagus, and the garden will be set for winter.