Though October finds my gardens looking rather tired and disheveled, I still treasure every bit of color and foliage. But by later this month, the good-byes will be over. The gardens will be thoroughly blackened by frost and I can get busy again, putting them to bed.

Don't be overwhelmed at the thought of yet another chore before winter sets in. Even if you do nothing in the way of fall cleanup and mulching, your garden will probably be fine. But if you do have a few hours to spare, here are the fall tasks I find most beneficial:

Why Cleanup? Removing spent plant material from your gardens reduces the amount of disease spores and insect eggs that could cause problems next season. Once you've had a hard frost, pull out and compost all annuals (if they're diseased, keep them out of your compost pile). Cut perennials back to about 4 inches high. This stubble will help you find the plantnext spring, and will also keep mulch and snow over the crown of the plant.
Why Mulch? The biggest benefit of winter mulch is that it helps to keep plants dormant and moderates temperature fluctuations. If you usually have plenty of snow cover from December through March, you probably don't need to mulch. But in most parts of the country, winter brings freeze/thaw cycles that cause frost heaving and lots of plant damage.

Which plants should be mulched? I'll admit that I mulch selectively, focusing on my roses, garlic, mums, newly settled plants and a couple tender favorites. The amount of mulching you do in your own garden depends on the severity of your climate, the condition of your soil, the kinds of plants you have, the amount of mulch materials you have on hand, and how much time you can devote to the task. Remember that in most cases, winter mulching is one of those good but not essential tasks. If you can't mulch everything, concentrate on plants that may be marginally hardy or those that you especially treasure.

When to Mulch. If you do mulch, don't rush it. Plants need to enter dormancy slowly and completely. Mulches should be applied only after the ground has frozen, which in many areas is around Thanksgiving or the first week of December. Once the ground begins to thaw next spring, it's important to pull the mulch several inches from the crowns of your plants. This will give newly emerging growth access to sun and good air circulation.

What to Use for Mulch. An effective winter mulch must be water and air permeable so as not to smother the plant below. Non-matting winter mulch materials include: shredded leaves, evergreen boughs, pine needles, salt hay, weed-free straw, chopped cornstalks, wood shavings and compost. Do not use whole leaves; they pack down and can suffocate the plant they're intended to protect. For most plants, 5 to 6 inches of mulch should be adequate. Roses should have a full 10 to 12 inches of soil or compost mounded up over the crown of the plant.


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A layer of polyester or polypropylene garden fabric or burlap can be used to hold organic mulches in place. Many professional growers cover container-grown plants and beds of young perennials with an extra-thick garden fabric, such as GardenQuilt. I use GardenQuilt in my own garden to insulate my fall-planted garlic bed.

In the vegetable garden, I spread a 12-inch-thick layer of straw over my carrots and beets. This keeps the soil from freezing so I can continue harvesting into December. Moisture is Important. Most winter plant damage is due to moisture problems, not cold temperatures. In dry climates such as Colorado, as much as 95 percent of the winter plant loss is due to dehydration. In wet climates such asthe Northeast and Northwest, many plants get waterlogged and either suffocate or are damaged by frost heaving.

All plants need to go into the winter well hydrated. If you're gardening in a dry climate, or your area is suffering from drought, water your plants thoroughly until the ground is well frozen. Very dry areas may benefit from monthly watering right through the winter (even if the ground is partially frozen).

Plants in wet climates face the opposite problem. You can't stop the rain, so the only solution is to improve drainage. Add organic matter to the soil, plant in raised beds, or just be careful about siting your garden and plants. I've found that certain plants are more intolerant of wet soil than others. Russian sage (Perovskia) hates my heavy soil and though it is supposed to be hardy in my zone, I have yet to get a plant through the winter.

Wind Protection Makes a Difference. Cold, drying wind is another major hazard for plants. If your garden is in an exposed area and/or you get lots of dry winter wind, your plants will really appreciate some wind protection and a layer of mulch. Shrubs, fences and other structures effectively buffer the wind and help maintain a protective soil cover of mulch or snow. You can also create a temporary windbreak from netting or burlap.

That's the lowdown on winter mulches. Prune things back and cover up what you can. But make sure to leave plenty of time for apple picking, leaf peeping and the other pleasures of October.

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