I don't mulch at all. It's not the cold as much as poor drainage, "critters", and heaving (which can expose roots to the elements) that cause winter die-off for me. Critters (small rodents of various sorts) are by far the biggest issue and they do love the areas where dried plant material and snow have collected.

Of course I must say that I do not clean my gardens in the fall. I leave the dead and dried plants for spring clean-up. The reasons I do that are 1.) winter interest of the dried plants - some look nice snow covered and even without snow it is better than barren ground to look at. And, 2.) the plant will "mulch" itself with whatever is natural and needed for its survival.

I have long, cold winters and I do get subzero temps albeit not as much or as cold as yourself. I would suggest mulching only if something is marginally hardy in your zone.

FataMorgana

My winters are not nearly as bad as yours so take my advice with the proverbial grain of salt.
I mulch everything but that is as much to prevent weed competition and retain soil moisture as anything else. Some say that if you did not already mulch before winter then to wait until after the first freeze and then to mulch as a way to keep the freezing in place instead of the back and forth. The alternating freezing and unfreezing does a lot of the heaving. I haven't done this myself however. I usually do my mulching when I first transplant plants or first clear an area. I do my follow up mulching (and everything else) when I get around to it. I generally don't do mulching in the dead of winter since my wood chip piles (my free mulch of choice) get frozen into solid blocks. I never let mulch touch the stems of the plants.

Agree with Fata, although I've been known to add extra leaves, especially when I lived in OH. Ash and maple leaves disappear over winter and that's what mother nature "uses." I prefer to add mulch in the spring cuz then it seems like something "fun to do" after being inside for a while.

Another reason to clean up in the spring is so you can see where everything is.

Re: the Anise hysop, I have found that yes, individual plants frequently do not survive the winter, but that volunteers from seed can be abundant-sometimes too abundant!

+oM

wisconsitom, that was my worry. My agastache plugs have not flowered yet... which means if I lose them this winter, I won't have anything for next year. I've read about taking agastache cuttings. Anyone think this would work for overwintering some for next year?

thanks for all the input, everyone.

I mulch a lot. It keeps down annual weeds that I don't want springing up in my perennial beds.

I do heavily much some plants for winter protection, but typically they aren't natives. The natives generally won't need mulch for winter protection, but it won't hurt them either. And mulch has other benefits... weed control, adds organic material to the soil, helps minimize wide fluctuations in moisture and temperatures of the soil.

The woodland natives are accustomed to growing in a bed of leaf litter. My mulch of choice is shredded fall leaves.

I forgot to mention that mulch looks nice too.

I mulch Young plants. Old plants, All plants. I have an oppressive, sun stealing, "way too big" for its yard @#$%! Pin Oak Giant Tree planted next door close to the property line, to my irritation because every stinking leaf ends up in my yard (and gutters on my flat roof needing constant cleaning) and not theirs which is just lawn. But, it does provide mulch whether I want it or not, sometimes three feet deep and I don't have to do a thing. I have no choice in the matter unless I want to rake weekly. Did I mention how much I hate this tree?

I am jealous... I love fall leaves... mainly because I use them for mulch.

I grow lots of woodland plants in my shady yard and they love shredded leaf mulch.

You can have as many of these leaves as you want for free. This tree dwarfs their house visually, its a problem of scale and proportion. People really should think more carefully before planting trees. Its a particular complaint of mine. Sometimes a single tree is preferable, for instance, not 4 or 5 different kinds and shapes in one front yard struggling for sunlight and fighting for attention. I like well chosen trees.

I grow full sun loving SW native plants that need drainage, air circulation and have a mostly all gravel xeroscape with lots of prickly pear cactus, agaves, yuccas and native grasses mixed in that are not fun to clean out. These leaves are not my friend and I spend all winter cleaning them away and raking boat loads off the roof which has a parapet that holds them, so the gutters stay clear and won't leak in the house when it freezes. I haven't met a gardener or homeowner yet without some problem to put up with however.

I wanted to add on the mulch question that snow makes an excellent mulch when its there all season like in Colorado. Here we experience a lot of very warm days alternated with cold dry windy ones. Mulch is a good way to protect the freeze/thaw damage and cold drying winds or freeze damage. Here it keeps the temperature from too great of a fluctuation for the plants. Our ground can get pretty dry in winter and warm up pretty hot in the sun and doesn't really freeze much except in shady spots, sometimes not at all. Mulch would be good here but maybe not necessary where you are. I have never had problems with rodents etc, and mulch. Plants always look nice, green and fresh when you pull it away in spring. I recommend some kind of protection. I have used thick polyester quilt batting on less cold hardy cactus and succulents because it wicks away moisture. It works great where you need something dry to avoid rot problems.

Fall leaves yes. I love them too. Pin Oaks drop the suckers all fall, winter and early spring long. I call this a messy tree. OK, I'm done.

I can appreciate cactusgarden's frustration. But, we all have our challenges. I love leaves so much that I go out every fall and steal them from the curb. I also covet the piles that collect along the curbs from the wind. My greatest yearning is for the pine needles that drop in the fall. They make the nicest mulch because they don't blow away. I wish I could buy a truckload of pine needle mulch. And it smells so good in the sun! OK, I'll stop now.

Martha