Make a rhubarb pie. There are enough pumpkin pies out there right now, and there's plenty of rhubarb still taking up real estate. With the recent cooler weather, it's continuing to flourish and looks amazing. Traditionally, rhubarb is a spring crop, and you stop harvesting after Fourth of July. This is because if you harvest too heavily, it stresses the reserves the plant is building up, and you get less to harvest next year. But I'm looking at these plants, and I'm looking at the weather forecast, and it's all going to be dead in a few weeks, anyway — so why not make pie? Because it's fall, I use a knife or pruners instead of just breaking off the stems; the roots seem a little more sensitive now, and they don't have a summer to recover. On the other hand, if you accidentally yank up the whole plant, prune off all the substantial stems, and replant the crown in a different place in the garden to start a new patch. Mulch well, but don't cover the crown. Compost the leaves and any of the pencil-thin stems or stems that are either woody or seem to have no substance. Use only solid, juicy stems for the pie.
Look at your evergreens. Yew, that ubiquitous foundation shrub of the '50s, is starting to look more than a little ragged. Summer growth sticks out a foot or 18 inches and desperately needs to be hacked back. But if you wait another month or so, the greens from this plant are absolutely wonderful for home decorating. Although they don't smell like balsam or pine, they will stay green until Valentine's Day. And you get double the decorating power, since the underside is a totally different color.
Water, weed, and mulch.