Why Mulch in the Winter?

snow covered plantsGardeners know why they mulch in the growing season. Mulch keeps the ground cool during the hot months, helps retain moisture and smothers weeds. As organic mulch breaks down, it puts nutrients into the soil. But why would anyone mulch around a plant or tree during the winter when nothing much is happening? Here are some reasons:

Protection From the Weather

People mulch in the winter for much the same reason they mulch in spring and summer. The mulch protects the roots of the plant from the weather. Mulch regulates the temperature of the soil during the winter and prevents frost heaving. This is when the soil freezes and thaws and actually lifts the top of the roots out of the ground. This exposes them to frost, which can kill the plant even if the rest of the plant can stand a bit of frost. If the area gets a lot of rain in the winter, mulch keeps the soil from being washed away. Mulch also keeps a plant dormant by keeping the ground cold during a warm snap. Mulch applied in late winter also stops weed seeds from sprouting in the spring.

Though they may not break down as fast in the winter as they would during the warm months, organic mulches such as wood chips still break down and get nutrients into the soil around the plant. They also provide food for earthworms and beneficial microorganisms which break down the mulch and enrich the soil for the upcoming spring. It is especially useful to lay woody mulch such as bark mulch, hemlock mulch and hardwood chips in the winter. This type of mulch applied in spring binds nitrogen as it rots and doesn’t allow it to get to the roots of the plants as quickly as it should.

When to Apply Winter Mulch

Gardening experts claim that winter mulch is best laid after a hard freeze, which would be a night that gets colder than 25 degrees Fahrenheit and kills even the toughest annuals.

How to Apply Mulch

As with spring and summer, mulch should not be thicker than 4 inches if it’s made of a coarse material such as bark mulch. A lighter mulch is an inch or two shallower. It shouldn’t touch the crown, which is the place where the stem and the roots meet. An exception to this would be hybrid tea roses whose crowns should be buried in mulch in the cold season. A gardener can use a rake with springy tines to spread out a lot of mulch beneath a tree or scatter it with their gloved hands around smaller, more delicate plants. Depending on the type of tree, a good layer of mulch spreads about three to ten feet in diameter around the base of a tree, and 2 to 4 inches deep. The mulch should not touch the tree.

Types of Mulch

Besides bark mulch, other types are hardwood chips like oak, cedar and hemlock, and softwood chips like pine chips. Shredded leaves decompose quickly, and are at best, a temporary solution. Pine needles and pine boughs are not only aesthetically pleasing but hold in moisture. Pine and other evergreens are especially good for plants that thrive in acidic soil, but be careful to remove boughs when spring comes. Straw is light but keeps the ground warm and is inexpensive and plentiful. It is preferable to hay, which can hold weed seeds. Whatever type of mulch is chosen should be from a source that knows that it is free of chemicals and disease.

Inorganic mulches can be anything that doesn’t hurt the plant, including river rock, glass chips, lava rock, coconut shell, old coffee beans, black plastic or ground up old tires. Inorganic mulch doesn’t need to be refreshed, even though it needs to be removed when winter is over.

When you buy mulch from trusted local suppliers, you know you are getting genuine and affordable products for your gardening and landscaping needs. The Melvin Mulch Company is among the best local source in Milwaukee for natural landscaping and beautification of your yard. Melvin Mulch also provides valuable pointers about gardening, mulching, and the benefits of using different mulching materials for your soil’s surface. Looking to buy good winter mulch? Just call Melvin at 414-856-9077 today.

Photo by USDA NRCS South Dakota from Flickr using Creative Commons license.