Bring in container plants.
Your container plants won't survive the colder days of fall sitting out your porch. Bring perennials indoors, but first make sure they are free of pests and diseases so you don't endanger your houseplants. Place the perennials in a window where they'll receive their proper allotment of light. Some plants—for instance, rosemary—go dormant in the winter and can be kept in a garage or basement until the growing season begins.
Related: 30 Ways to Color Your Yard This Fall
Clear out the summer vegetable garden.
Even if your summer vegetable garden has dwindled down to dried tomato stalks and withered bean vines, your backyard farming duties aren't over yet! If left where they stand, dead garden plants can attract pests that could harm your chances of a good crop next year, so clear them out. If they're not disease- or pest-ridden, go ahead and compost them; otherwise, toss them in the trash.
Plant new trees and shrubs.
Early fall is the best time to plant a new tree or shrub. With the heat of summer long gone and winter still yet to come, the plant's roots will have time to become established before the ground freezes. Mulch the base of the new tree with wood chips to retain moisture, and supplement fall rains with additional watering when needed.
Related: 9 of the Best Shrubs for Any Garden
Get rid of weeds
Herbicides can be more effective at killing certain types of weeds in autumn than in spring, so you should take advantage of that vulnerability. Treat weeds with an application of post-emergent herbicide, and consider also applying a pre-emergent herbicide, which will prevent other weeds from sprouting. By killing off weeds now before winter sets in, you'll be laying the groundwork for a healthier, less weedy lawn and garden next spring.
Related: 7 Weirdly Effective Ways to Weed
Cover tender plants.
Certain plants, such as azaleas, rhododendrons, and smaller evergreens, benefit from being protected from freezing conditions. Add mulch around the roots of sensitive plants to insulate them and help them retain moisture. A well-hydrated plant is in a better position to withstand cold temperatures, so water regularly, tapering off as temperatures get cooler. If necessary, some plants can be bundled in burlap or another insulating material until they go into winter dormancy.
Related: 10 Ways to Weather-Proof Your Garden
Fertilize your lawn.
It may seem strange to feed your lawn before it goes dormant for winter, but, in fact, a fall application of fertilizer can protect your lawn over the cold months and help it look healthier come spring. Choose a nitrogen-rich fertilizer designed for fall feeding, and apply a thin layer evenly to the lawn a few weeks before the ground freezes.
Deadhead and collect seeds.
By now, many of your beloved annuals and perennials have probably gone to seed. As you deadhead and prune back dead growth, collect seeds from your favorite plants. Consider leaving seeds of some plants—coneflowers, for example—where they stand, as they can provide backyard birds with winter sustenance.
You can't stop the cold from coming into your garden, but you can help protect your plants from exposure by applying a generous layer of wood mulch. Mulch insulates the root systems of vulnerable plants, keeping them healthy and strong, and improving the chance that your perennials will survive the winter.
Drain the water lines.
If you don't drain and switch off your sprinkler system, hoses, and outdoor faucets before freezing temperatures strike, you could cause permanent damage to them. Drain hoses and store them in the shed, garage, or basement until spring, and consider covering outdoor taps with foam pipe insulators or foam faucet covers for added protection.
Get Ready for Winter
Tending to those end-of-season yard chores will make spring clean-up a lot easier.
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