In locations that have freezing temperature levels, winter season mulching varies from mulching done during the growing season. Most gardeners mulch their gardens in the spring to reduce weeds, maintain moisture, and warm up the soil. While some may prefer spreading a layer of compost during the fall season, the main reason for winter season mulching is to safeguard your plants from the extreme conditions of winter freezes, defrosts, and winds.

Why Mulch the Garden in the Winter season?

The primary concept behind winter season mulching is to maintain a frozen ground by protecting it from the heat of the sun. This helps create steady temperatures that will help keep the plants dormant and prevent new growth during brief warm spells. An early new growth is likely to result in winter dieback which is why you want to buy mulch for your garden when the temps start dropping. Mulching during this time will aid in conserving as much water there is in the soil which hopefully, should have enough water if you’ve been watering your garden beds right before the hard frost.

What Can You Utilize to Mulch the Garden in Winter season?

Any insulating material will suffice when mulching in the winter. Do note that you’ll need to get rid of the mulch or at least rake it aside once spring season arrives. Pine needles, shredded mulch, and shredded leaves are some good examples that are relatively easy to work with. If your ground does not freeze till after Christmas, you can make use of cut boughs as a mulch covering. Those branches are great since they can easily be removed as soon as spring arrives.

Snow is also a good mulch since it acts as an insulator and protects your plants. Some plants will just collapse onto themselves and serve as self-mulches. If allowed to do so, Chrysanthemums are an excellent choice and will survive best whilst serving as mulches for your other plants.

When Should You Use Winter Season Mulch?

Mulching to safeguard most perennial plants is done when the soil has actually begun to solidify, which is typically after the first hard frost. A hard frost is a period wherein the temperatures drop below 25°. One indicator of hard frost is when you see the remaining hardy annuals crumble and turn brown in the morning. During this stage, your perennial plants should be well into dormancy and the mulch will help discourage tender new growth. This is the perfect time to spread out a 2 to 4-inch layer of mulch around the base of the plants.

Avoiding Desiccation

Some evergreen plants like viburnums and rhododendrons can become desiccated by harsh winds. To protect the branches and buds, you can spray an anti-desiccant over them or wrap them with burlap. If you do decide to wrap your shrubs, make sure there’s enough space between the plants and the burlap or else the latter will freeze onto the branches and create a new set of problems. For additional insulation, you can also choose to fill in the spaces with leaves.

Woody plants don’t need as much protection as herbaceous perennials. However, a 2 to 4-inch layer of shredded bark mulch or garden compost will go a long way towards conserving ground moisture as much as possible. Keep it a couple of inches away from the stems to avoid inviting unnecessary rodents like mice and voles. Also, mulching up way too close to the stems can lead to excess moisture buildup around the plant which can encourage diseases to manifest.

Avoiding Heaving

When the ground consistently defrosts and freezes, it expands and contracts. This can somewhat loosen the roots of the plants underground to where they eventually get pushed up the surface. This exposes the plant’s crown and roots to cold winds and freezing temperatures. Your best bet would be to wait until the top of the plant has died back and the ground has become frozen before applying mulch.

Avoiding Erosion

Winter mulches protect the ground from soil erosion and compaction brought about by heavy rains.  Preferably, you should plant a winter cover crop and let it sit before you till it during the spring season. If you elect to not plant a cover crop, it would still be helpful to spread out a layer of garden compost, manure or shredded leaves. Winter mulches also create an insulating barrier between the soil and air, which helps protect plant roots from varying degrees of soil temperature fluctuations.

Removing Winter Season Mulch

In general, removing winter mulch should be done during spring when all the imminent dangers of a hard frost have passed. While this can sometimes be difficult to judge, you can tell the hard frost has come and gone when the ground starts thawing and the smell of mud is lingering in the air. This signals that it’s time to start raking the mulch to let the ground warm up and encourage new growth from the plants.