F ILL IN THE BLANK: ___________ is an evergreen ground-covering conifer that can tolerate some shade and minus-30 or colder. I guess I gave away the answer in the headline, but you get the idea: It’s an unusual set of traits. And Microbiota decussata, the so-called Siberian cypress, distinguishes itself just a little further, turning a bronzy-purplish cast in winter.
Unlike the ubiquitous groundcover junipers, Microbiota is lacier-textured, almost Arborvitae-like, and does not hug the ground so flat as do many junipers, arching in a more graceful manner. My oldest plants are more than a foot tall at the tallest spots, and more than 8 feet across (I have read that they can get to 10 or even 12 feet wide and a couple of feet high). It is good for holding banks, which is how I use it on my hilly site, such as just above and beyond the pictured Buddha (if one can be above and beyond Buddha, that is).
The plant was first discovered near Vladivostok in the 1920s, above the treeline, where it survived the deep cold of Siberian winters, making it a Zone 3-hardy creature here.
Although it is a groundcover species, don’t expect it to grow in the dark: That was the mistake made at first when Microbiota reached the American market in any numbers maybe a decade ago. Saying a plant can handle some shade is different from saying it’s a shade plant; this one wants half a day of sun or more, I think. In warmer zones, protection from afternoon sun is important, and in fact Microbiota isn’t a fan of the hottest zones at all.
Though Microbiota (seen above in winter color) is said to have few if any pest and disease problems, I will confess to this: I have killed a number of them, without ever learning why. What was meant to be a whole bank of Microbiota simply didn’t choose to be that way, and only about half of the ones I planted thrived. In another spot, I had the same experience. Hmmmm…was it something I did, or had this load of plants suffered some insult or injury en route to me that didn’t show itself until later?
I will never know. (A familiar refrain in gardening: You often never know; the thing just dies.) Give Microbiota well-drained but not dry soil, more sun than shade, and remember: Though it won’t happen instantly, these plants get big, so give them room. (A number of my other recent “Beloved Conifer” posts are listed below, by the way, and there is also the slideshow of them.)
beloved conifer: the concolor fir 
beloved conifer: chamaecyparis obtusa ‘crippsii’ 
Another great plant. I’ve planted them in several yards and either they do well or they fail miserably. They seem to have a bit of a Goldilocks complex. Moist soil with good drainage, but not too dry or wet. Bright light but not too hot.
My best specimens are on the north side of my house where they get morning and afternoon sun in summer and shade all winter. The sandy loam soil is sloped, but they get extra water from the roof line.
I’ve found they hate having leaves on their branches over the winter. If the leaves aren’t completely removed, branches die.
@Ted: Glad it’s not just me, but the *Goldilocks* thing at work. Thanks. :) Funny how some plants are just that way, isn’t it?
@Abby Jane: This is a very good observation, thank you. I think I only semi-consciously realize that, and will be even more careful. They are in a windswept spot and leaves blow on again and off again all winter, so it’s tricky. See you soon!
I know it’s beside the point, but I have to say how reassuring it is to hear “the thing just dies,” even for master(ful) gardeners. I have been lamenting several inexplicable deaths this spring with a “why do I even bother?” attitude. New attitude: “Oh well, better luck next time!” (I am surprised, though, to hear that many gardeners keep planting “iffy” things. I am not very forgiving, it seems. One strike, two at the most, and you’re out!)
Hi, Christine. Trust me, even the *real* experts (my mentors, and their mentors and their mentors’ mentors) lose plants every single year. I think 3 strikes is probably a fairer plan, if you can stomach it. So many variables at work: soil, rainfall, temps, how bad the winter is that year, what condition the poor things arrived in…and on and on.
I have one that has been struggling in the same spot for about 20 years! It won’t prosper and it won’t die! Saw some out in Mill Valley, CA that were enormous! Never too hot in that area!
In the front of my house is a hill/slope that was planted with junipers — two varieties — about 20 years ago. One variety started to die off as the sunny slope became a shady place. (from the maple that was planted after the junipers and is growing above them). So, after two experts recommended the microbiota decussata as a replacement, I had them installed last summer. And, I LOVE them!! Love the way they look and that they don’t prick me. They are soft to the touch, a wonderful thing. So far they look good after their first hard winter, so I hope they stay healthy in this spot. Thanks for mentioning their dislike of leaves as that is a problem for me. I will have to try and keep them free of leaves next winter.
In the Washington DC area people avoided Microbiota because it would look good for a few years then start to brown out; many blamed our neighborhood’s heavy clay soil. When I moved to the Eastern Shore of Maryland (well-drained, sandy, acidic soil) I planted five in a shady site to offset the effects of our hot & humid summers. They looked great for about five years and now … two are dead and the remaining three continue to brown out. I’ll keep the leaves off this winter and see if that helps, but it seems this Eskimo will never be a southern belle.
Welcome, Nancy. I guess I am not alone, and I am certainly in a much different climate than either of your trial grounds with Microbiota. Oh, my. Thanks for sharing your experience, and do come again soon.
Does anyone know if these are at least moderately salt tolerant?
Welcome, Linda. I have never seen it listed as such, but that doesn’t mean anything certain. However, based on its native habitat it’s hard to believe it will love much salt. See you soon again, I hope.
Hi – I am a new gardener (my first year) and have planted 2 and just bought a 3rd to transition from some boulders down through a root heavy/acidic soiled slope that gets morning sun. A really basic question: how deep should I plant? Is it okay if the bottom branches touch the ground? We just got heavy rains on the east coast and these branches are muddy – I’m afraid of promoting rot or disease. Any ideas? Thanks.
Welcome, Abby. A good question. The idea is to end up with the plant at the same level in the ground as it was in the pot — so the top of the former rootball (the big hunk of roots and soil you took out of the pot) should be approximately where it was before, maybe a tiny bit deeper but not much. In many low-growing or creeping plants, you are right: the branches will touch the ground, especially at first. No worry. Don’t bury them though. :) See you soon!