Should You Mulch in the Winter?

Mulching isn’t only important in the spring. There are plenty of reasons to apply mulch in other seasons, including the winter.

Why Mulch in the Winter?

Winter mulching is a critical tool for gardeners to protect plants against frigid conditions. Soil under the mulch doesn’t freeze, and that allows the plants to absorb more water. Here are some mulching tips to help you get started with the job.

“Mulch is a standard form of winter protection for many shallow-rooted plants, and young or tender perennials,” says Leonard Perry, Ph.D, an extension professor emeritus in horticulture at the University of Vermont. “While in summer it is effective in retaining soil moisture, preventing erosion, and controlling weeds, in winter it acts as insulation for the soil and plant roots.” Although mulch can help with winter weeds too.

When Should You Apply Winter Mulch?

When to apply a winter mulch depends on the region where you live. Generally, spread winter mulch just after the first frost, according to Jeff Gillman of FineGardening.com.

“By putting mulch down at this time, you will help stabilize the temperature of the soil right around freezing,” wrote Gillman, an associate professor of horticulture at the University of Minnesota.

“Applying mulch too soon may delay freezing and encourage heaving and thawing. Applying it too late may cause the roots of plants to experience temperatures below that which they can handle.”

What Can You Use to Mulch in the Winter?

“Great mulches for winter include bark chips, shredded bark, straw, evergreen boughs and other loose, coarse-textured organic materials,” according to OregonLive.

How much you use is more important than what you use. Perry suggests applying a two- or three-inch layer.

Removing Winter Mulch

Know when to remove winter mulch depends on the climate of your region and the start and end frost dates. However, there are some telltale signs.

“Walk your garden and see if the ground is thawing out,” according to RelsLandscaping.com.

“When the air is warmer and the threat of severe cold is behind you, this is the perfect time to remove that mulch from your perennials. Leaving the winter blanket in place is likely to smother them or encourage the growth of harmful mold — removing the mulch will allow your perennials to grow and thrive.”