Even though the growing season is coming to a close, autumn is a busy time of year for gardeners. It brings shorter days, cooler weather, colorful foliage, and a variety of garden-related tasks. Fortunately, this season also offers great weather for working outdoors and the opportunity to tidy up your garden and prepare it for winter and the following spring.
Autumn mulching has an array of benefits, from practical to time-saving to aesthetic. Mulch helps your plants stay healthy by ensuring a healthy soil system. Mulching saves you time and effort because it helps keep the soil moist and controls weeds. As a bonus benefit, it hides bare soil and looks great too!
Not every garden needs mulch, however, and different materials have different uses. You will find uses for lighter and heavier debris, depending on how fast you want it to break down or how durable you need it to be. Autumn applications can use any type of biodegradable material, but be sure to choose the best material for your specific beds.
Let’s check out these great reasons you’ll want to add mulch to your garden this fall!
Keep Roots Moist
All plants need some amount of sunlight, nutrients, and moisture. Mulch is useful any time of year to trap moisture so your plants can use it. Even during the winter, when your plants are dormant, your plants’ roots still need a bit of moisture.
Mulch provides a protective barrier between the soil surface and the drying effects of the sun and wind. It reduces evaporation and allows the ground to hold moisture longer, so you can spend less time watering. In the winter, when the air is cold and dry, fall mulch applications will give your plants a healthy layer of protection so they won’t dry out.
Protect Plants From Frost Heave
Frost heave is a process where shallow roots shift upwards to the surface or above it. Frost heave is the result of a natural environmental cycle where the water in the soil repeatedly freezes and thaws. This freezing and thawing causes expansion and contraction, thereby causing your crops or ornamentals to shift.
Frost heaving disturbs and exposes the roots and crowns, possibly causing damage or death to your perennials. Species with shallow root systems and those that have not yet become firmly established are most prone to frost heaving.
When you mulch around your garden in the fall, it offers a blanket of protection from sudden temperature extremes. Moderated temperatures help keep the ground stable, so it’s less likely to freeze and thaw repeatedly. If you live in a climate where the ground doesn’t freeze, you won’t need to worry about frost heave, but frost heave can occur anywhere else with freezing winter temperatures.
Protect Roots From Severe Weather
If you’ve done your research and chosen hardy perennials, you’re probably expecting your garden perennials to return year after year. Even if your species are cold-hardy in your region, they still appreciate some protection from the winter elements. Unexpected deep freezes can still kill some species at the colder limits of their range.
Fortunately, fall mulching will help protect your garden from harsh winter extremes. The extra layer helps to regulate bed temperatures and acts as a buffer between the elements and the roots. The tops of your perennials and even some of your more sensitive shrubs may die back completely in the winter, but as long as the roots are protected, they’ll spring back to life again when the weather warms.
Suppress Weeds
Most gardeners won’t list “pulling weeds” as their favorite gardening task. However, weeds are everywhere, and weeding is unavoidable. Luckily, there are some simple ways to suppress weed growth in your garden.
One big benefit of applying mulch in the fall is that you’ll have less weeding in the spring garden. New weeds start growing in the winter and are relentless as the year progresses. Apply a three or four-inch layer of mulch to your dormant garden beds and pathways. You’ll still get some weeds, but there will be many fewer than if you left bare ground exposed. There are always weed seeds waiting for an ideal opportunity to sprout, and mulch will help suppress them.
Help Prevent Erosion
Erosion doesn’t just happen on bare hillsides or along stream banks. Anywhere the soil is exposed to wind and water, it can be damaged or lost. Healthy soil is critical to gardening success. When your dirt gets worn and washed away by water, wind, and foot traffic, you’re losing this valuable commodity.
Mulching helps protect the bare ground from erosion. This is especially important in areas where you don’t have plants already in place, helping hold the soil together with their roots. Use mulch to protect the soil around your recent fall plantings, areas that are dormant or unplanted for the winter, and larger unplanted areas such as garden paths.
Improve Soil Quality
Use organic, biodegradable mulches are proven to improve soil quality. Natural mulches, like compost, wood chips, pine needles, and wheat straw, work with the natural decomposition process to enrich your garden over time.
As these natural mulches break down into smaller and smaller particles, they add organic matter, which helps loosen the lower layers of a bed. They also release nutrients to give your crops a very slow-release boost of essential nutrients. Mulches also increase the presence of earthworms and other beneficial creatures, which help aerate the ground and improve air and water flow underground.
Over time, mulching around your trees, shrubs, perennials, and annuals helps them thrive. Mulching with organic materials this fall will give your garden a head start when everything comes back to life the following spring.
Fall is a Great Time for Outdoor Work
Yes, this is an excellent reason to lay down garden mulch in the fall. The weather and temperatures in the fall are highly conducive to being outdoors. You may already be out working in your garden to complete other autumn tasks such as pruning, planting cover crops, raking leaves, and pulling weeds. If you think fall is already a busy time, spring is usually even busier.
Rather than procrastinate until spring to apply mulch, do it in the fall to take advantage of the many other fall mulching benefits. You’ll get the job finished, your garden will be ready for winter, your plants will enjoy the benefits of mulch, and you’ll save yourself time when spring rolls around.
Make Use of Fall Leaves
The seasons are changing, the leaves are falling, and you’ve raked them into piles. Now what? Turn those leaves into free mulch!
Use leaves around the base of trees and shrubs, but use caution here. Avoid using leaves that are infested with pests or fungal diseases, as these will harbor future generations of those same problems.
Use leaves to establish or maintain pathways. A thick layer of leaves settles quickly and creates an excellent weed-blocking layer. You’ll need to reapply leaves each fall because they break down quickly, but this just offers you an annual use for your fall leaves.
Leaves also work well as mulch in your garden beds. If you have a mower, try shredding the leaves first before using them as mulch. This will help them break down faster and allow more air and water penetration than whole, unshredded leaves.
Pleasing Winter Aesthetic
There are a great number of practical benefits for mulching in the fall. There are aesthetic benefits as well. A uniform layer of natural-colored mulch looks great. It hides bare soil, ragged stems, and uneven ground. Mulching around your perennials, shrubs, and trees adds a uniform layer of fresh, natural substrate that helps increase curb appeal during the winter when gardens typically look least attractive.
Frequently Asked Questions
The ideal depth for your project ranges from one to five inches. If the mulch is too thin, weeds will work their way through. If the mulch is too thick, it creates a barrier that prevents water from penetrating through to the soil.
If you’re trying to smother weeds along a walkway, you can apply a relatively thick layer, perhaps four or five inches deep. For most gardening projects, such as mulching garden beds to protect your soil and plants for the winter, three to four inches is a good target depth.
For freshly seeded areas or places you want your flowers to reseed themselves, consider a very thin layer of only an inch or so. This won’t keep weeds away but it will at least preserve soil moisture and help protect the soil.
In most cases, you won’t need to remove any mulch in the spring. If you’re using mulch to protect tender perennials from winter freezes, you may have put a thick layer of mulch over them in the fall. If this is the case, remove some of the mulch in the spring so your plants have a thinner layer over them when the weather warms. This will allow them to poke through when the time is right without smothering them under too much material.
Generally, it’s safe to wait until after the first fall frost. This allows your annuals and perennials to grow freely until hit by the first frost. Mulching after the first frost causes the least disturbance to your plants because you’ll be working around them as they go dormant for the winter. An added benefit of waiting until after the first frost is that there will be fewer pesky insects to bother you while you’re working outside.
For fall mulching around your flower beds, trees, and shrubs, stick to sturdy organic mulches that will slowly break down over time such as shredded bark or wood chip mulch. For dormant garden vegetable beds, use a mulch that breaks down faster, such as composted leaves or straw. If you have directly sown seeds to germinate in the spring, you’ll want a very light layer of permeable mulch, such as pine straw or hay so you don’t smother your seeds.
Be careful with hay, grass clippings, and raked leaves, especially if you aren’t sure of the source. These items especially can be full of herbicides and weed seeds. You don’t want to accidentally introduce a plethora of weeds to your garden, especially if you’re using mulch with the hopes of suppressing weeds.
There are many different types of mulch available for home gardeners. Whether you mulch in the fall or spring, each type of mulch has its own best uses. You’ll need to choose the material that makes the most sense for your particular landscaping needs.
Yes! Raised beds benefit from mulch just as much as the rest of your landscape. You’ll get the same benefits from mulching, no matter where you use it.
