In most parts of the country the gardening season is winding down and preparations are under way to put the garden to bed. That's a somewhat misleading phrase because, for instance, in my Chicago garden many plants (the witch hazels, creeping sedums, aster rosettes, and a few precocious snowdrops) are active in winter. Also, it is not yet time to pull the blanket of mulch over the garden. That comes next month when the ground begins to freeze. Much like with a toddler resisting bedtime, putting the garden to bed does not mean it's going to go to sleep. But the steps we take now will prepare it for the cold to come.
Leave plants standing only if they are appealing to you. If you like the tawny, swaying ornamental grass stalks, leave them. Personally, I enjoy the brown lily stems and watching the birds eat the seeds from faded prairie plants in winter. It reminds me that the garden is alive and will return. However, don't feel obligated to leave spent plants, particularly if you don't find them to be aesthetically pleasing.
If you have rodent problems, cut down all spent plants to eliminate nesting material. Because of the huge population of voles in my community garden, I even trim back my growing sedges. If not, the voles will nest in the plants and munch on their crowns all winter long. By spring the voles will be healthy and ready to breed, while my sedges will be devoured. But it could be worse. Rats and mice will also nest in garden debris.
Watering is only necessary for newly planted evergreens. Soak them well until the ground freezes to give them the best chance of survival. Reduce weed problems next year by pulling perennial weeds with rosettes or creeping stems, such as thistle, dandelion, bindweed, nightshade, burdock, and nut sedge. Annual weeds, such as amaranth, velvet leaf, and weedy morning glories, should be removed before their seeds ripen and drop into the garden.
Planting can be chancy this late in the fall, but there are exceptions. Dormant woody plants can still be planted. If cold weather is still a ways off, cover crops can be sowed in vegetable gardens. They help prevent erosion from rain and wind, improve soil tilth, and prevent leaching of nutrients from the soil. Cover crops in the pea family, like clover, alfalfa, and hairy vetch, also deposit nitrogen in the soil. While southern gardeners have a wide selection of cover crops to try, northerners typically choose buckwheat, ryegrass, annual rye, or hairy vetch.
Disconnect hoses from outdoor spigots. Lay hoses flat and drain any water from them. Roll them up and store for the season. Close spigots tightly to reduce drips. Gardeners in cold weather climates can buy spigot covers to protect against extreme cold that can burst pipes.
All garden chemicals should be properly stored and labeled. Place garden fertilizers, herbicides, and pesticides in separate plastic bins away from heat and moisture. In preparation for the coming snow, buy calcium chloride to melt ice instead of the usual sodium chloride or potassium chloride. Typical salts can damage plants and soil. Calcium chloride is an effective deicer, plus it's a beneficial soil amendment.