How to Mulch Your Garden in the Fall

coir mulch in wheelbarrow.
David Beaulieu

All your hard work maintaining your landscape and garden doesn't come to an end just because winter is on the horizon. In fact, some of the most important to-dos you can check off in your yard come in the form of preparing your soil ahead of the next growing season. From raking your leaves to mixing in mulch, the steps you take now will reap big rewards for your plants down the road.

Whether you prefer to use a "living" mulch or a more conventional type, your garden will surely benefit from the added protection, richness, and nutrition it provides. There's a long winter ahead (at least, if you live in the northern United States), and you want to ensure that, come spring, you'll be ready to plant when the opportunity arises.

Preparing Your Beds for Mulching

When all the plants in your fall vegetable gardens or annual flower gardens have been harvested or are dead, your garden mulching efforts can begin. Before you get down to business, there are a few things you want to do to prep your landscape for mulching in order to reap the maximum benefits from the process.

First, spend some time removing plant debris from your beds. This includes—but is not limited to—the stems and leaves of dead plants; any dead fruits, vegetables, or flowers that have fallen to the ground throughout the season; any weeds or other invaders. As you clean up your space, be on the lookout for anything that looks diseased—you'll want to take extra care to remove sick plants entirely so they don't infect next year's crop.

Pile all your plant debris into a compost bin or other collector, allowing them to break down to be used for nutrients going forward (Note: only do this if they're healthy and have died of natural causes. Diseased plants should never be composted). Use your clean garden or bed as an opportunity to rototill your soil, mixing in any additional nutrients (like garden lime) or soil amendments you may need.

Choosing the Right Mulch

Contrary to popular belief, selecting the right mulch for your garden is not a one-size-fits-all scenario. Depending on the types of plants you're tending to, your location, and the unique needs of your space, you may have to make adjustments to your soil or choose between several different methods of mulching.

At its core, mulch is simply any organic material spread over the top of your soil as a protective and nutrient-dense covering. The possibilities are endless when it comes to mulch ingredients, and many include a mix of bark, shredded or chipped wood, pine needles, grass clippings, shredded leaves, straw, compost, and even newspaper.

The type of mulch you choose will largely depend on your garden's needs. For example, straw and hay are a popular pick in vegetable gardens, as they decompose very slowly and will last the entire growing season. Similarly useful, shredded leaves are a great mulch option and an ideal way to use up all that fallen foliage in your lawn come autumn (If you'll be using leaves as a garden mulch, shred them first by running the lawnmower over them before collecting). You can control or fix almost anything with the right type of mulch, from the temperature and moisture of your soil to its pH levels.

Another option when it comes to mulching your landscape is "living mulch." Synonymous with "green manure" and "cover crop," a living mulch is just what it sounds like—live plants that are grown in a planting bed and take the place of a conventional mulch. All you need to do to achieve a living mulch is to broadcast their seed after rototilling.

There are several instances where your garden may benefit from a living mulch over a traditional organic matter mulch (not to mention it's beautiful and essentially creates a winter garden). For example, if you're concerned that a large bed (typically a vegetable bed) might suffer from soil erosion over the course of the winter, you could grow a crop of winter rye on top of it. The roots of the winter plants will help keep the soil in place as snow freezes and melts.

Applying the Mulch

As a rule of thumb, the best time to begin thinking about mulching your garden or landscape is after the first deep frost. By laying mulch at this time, you'll ensure that the soil remains just around the level of freezing, allowing any remaining plants to go dormant without temps dropping so low that the plant succumbs to the elements.

To spread mulch, add numerous piles of your chosen material throughout your garden. Using your hands, spread the mulch evenly throughout your space, taking care to leave a bit of distance between the mulch and any stems or branches of remaining plants (which will help prevent rot). You want your final layer of mulching to be about three inches deep, so be sure not to underestimate the amount of mulch you'll need.