Winter Protection For Boxwood

Detroit-Garden-Works.jpgBoxwood is one of the most versatile and robust growing evergreens available for planting in my zone. There are a number of great cultivars.  Green Velvet matures at 3′ by 3′, and keeps its great color all winter. Green Mountain is virtually identical to Green Velvet, but grows to 4′ tall by 3′ wide. Buxus microphylla koreana, pictured above, is hardy in this full south sun location, and can grow to 5′ by 5′.  The winter color is a dull orangy bronze. Winter Gem boxwood is incredibly hardy, and grows slowly to about 4′ by 4′. The leaves are smaller, and narrower than Green Velvet.

DSC_4001There are lots of other hybrids available.  Vardar Valley is an outstanding hardy cultivar of buxus sempervirens. It matures at 1′ to 2′.  The leaves have a distinctive blue green color.  As it is a slow growing variety, it is not routinely offered for sale at local nurseries.  Most of the boxwood sold in my area is grown in regions where the season is long enough to permit 2 flushes of growth per season.  This means nursery can get a salable product faster.  Boxwood is graded by width-not by height.  A boxwood takes about 7 years to grow to an 18″-24″ size.  This makes them relatively expensive to buy, compared to other ornamental shrubs that grow quickly.

MG 2013 (29)Boxwood is indeed a versatile shrub. They make great hedges, as their growth is uniform, and they are very tolerant of pruning.  That tolerance makes them an ideal subject for living sculpture. Boxwood pruned into spheres, squares, cones and cylinders are striking and delightful.  The large boxwood in this landscape will be kept pruned in spheres.  The small boxwood will be allowed to grow together, and will be pruned flat. This garden will have a much different look in a few years. All of these boxwood are Winter Gem.  The fine textured foliage makes them ideal for pruning into a formal, strictly geometric shape.   DSC_1801Boxwood are quite friendly to other plants.  Provided care is taken in the selection of a cultivar for a specific site, they will stay in bounds. These boxwood rectangles are a beautiful foil for the clipped espaliered crab apples. If the face is pruned on a very slight angle out from top to the bottom, they will stay green all the way to the ground. A boxwood which is hard pruned into a specific shape will stay green on the interior.

boxwood-green-velvet.jpgBoxwood makes a fine tall ground cover under a tree.  They are quite shade tolerant. A small landscape such as this is all the more interesting for a change of level.  These boxwood are a welcome visual intermediary between the ground plane, and a linden which has grown to substantial size. That they are shade tolerant means they can be sited in lots of places.  Naturally grown boxwood make a lovely backdrop for ferns, hostas and shade tolerant perennials.  A boxwood provides a green backdrop for the earliest of perennials to appear in the spring.  The small textured foliage makes them a great companion for the bigger textured hellebores, and European ginger.

Aug 31 2013 (20)A boxwood would go so far to oblige a gardener who wishes to grow them in containers.  They do need large enough containers so there is room to grow.  The root ball of a decent sized and well grown boxwood might be larger in diameter that its leafy component.  Boxwood in containers need special attention to proper watering. They need to be well watered prior to freezing weather.  They will rely on water stored in the stems and leaves to survive they winter, as the water in the container cannot be absorbed when it is frozen.  Boxwood in ground has much more widespread moisture available to its roots, especially given how long it takes for the ground to freeze to any significant depth.  A boxwood confined to a pot needs regular water.

boxwood-hedge.jpgPruning boxwood takes more than a good eye.  A great job invariably involved the setting of level lines.  Relatively level boxwood has a forlorn and unfinished look.  This boxwood has been pruned level with the horizon, even though the driveway drops down to the street.  The boxwood at the bottom of this drive is quite a bit taller than those plants at the top.  Level boxwood has a serene and solid look to it.

August 12 2013 (11)Boxwood can help provide structure to a garden.  This densely growing shrub provides a simple and strong contrast to the garden elements.  This pruning is loosely formal, and softens the stone wall behind them.

Aug 31 2013 (18)I have written about boxwood plenty of times before – I do like them.  It was painful to see how many boxwood in my area were severely damaged or killed outright by our last winter.  Some were crushed by the huge snow loads.  Others in more exposed locations were damaged by the extreme cold.  That cold, in conjunction with sun and wind burned the leaves. Leaves that were completely desiccated, died. It took the coming of the spring weather to see how terrible the damage truly was.  Some of the boxwood at the shop died outright.  The damaged portions will take years to recover.

July 5, 2012 035If you have ever hung a boxwood wreath on a shaded door for the winter, or used cut boxwood in winter pots, you know those stems will dry out, but stay green until the temperatures moderate.  Like many evergreens, by the time a boxwood shows signs of stress, it is too late to remedy the problem.  Now that fall is approaching, I would urge anyone with boxwood in my zone to spray them with an antidessicant.  An antidessicant is a waxy coating with will slow the evaporation of water from the leaves in the winter.

boxwood-spheres.jpgI have heard talk that this winter looks like it may be a very cold winter.  Something like last winter.  Though boxwood is hardy in this zone, extreme cold, sun, and drying winds can damage them.  Though a boxwood may grow out of winter burn, that look is unsightly come spring.  If your boxwood are 15 years old, it will be very expensive to replace dead plants with new plants of the size you already own.  Last winter was dramatic evidence that winter protection for boxwood is a good idea.  photo (43)I recommend Vapor Gard.  It is widely used as an agricultural antidessicant. The main ingredient is pinolene, a natural polymer made from pine pitch.  It can significantly reduce winter burn.  You can buy it, dilute it 1 part to 20 parts of water, and spray it on your boxwood. If you have lots of boxwood, your tree care company can spray this for you.  It is best done on a dry day, before the weather drops regularly into the low forties.  The polymer coating will protect those leaves over the winter, and help them retain moisture.  Vapor Gard is a natural and non toxic spray widely used on crops, including cherries.  It is an easy way to protect your investment. Do read the label-it is not appropriate for every and any plant. I plan to spray all of my boxwood with it soon; one application will protect them the entire winter. The boxwood pictured above from this past spring-heartbreaking.   Interested further?   http://www.cdms.net/LDat/ld06L002.pdf

Comments

  1. Thanks for another timely post, Deborah. A question as to transplanting boxwood: for your zone if you have to or plan to, do you transplant in the spring or the fall?

    • Deborah Silver says

      Greg, If I am digging up and moving, I would wait until spring if I could. If I am planting new plants with undisturbed boxwood, I could plant now in a protected location, and spray. That said, you would have to make your own call for yourself. Best, Deborah

  2. Alison Wilson says

    Dear Deborah:

    Many thanks for the advance instructions useful in protection of boxwood hedges. What is your opinion on burlap protection and/or additional mulch coverage. If the predictions are correct, we had better hunker down and hold on for a tough ride.
    Thanks,
    A.

    • Deborah Silver says

      Dear Alison, burlap does help keep salt spray off of boxwood. Winter protection depends on where the boxwood are sited. I did not protect my boxwood at home at all, and I had no winter damage. They are sited in a protected location. I hate the look of burlap,so if I am trying to protect them from drying winds and cold, I prefer Vapor Gard. Extra mulch may just provide a cozy winter home for voles and other rodents-I would not do that. Best, Deborah

  3. joyce koreman says

    Deborah,

    Many thanks for this information about Vapor Gard. Usually, because of the wind, we construct a fabric protection as tall as the boxwood. But along the front walk we think we might need this
    on both sides, and that isn’t pleasant to walk past for all our winter months. My gardener’s heart
    would be crushed if we lost our design to our winter cold. I don’t know why we missed knowing
    about Vapor Gard.

    And about the roses: what can I do this year. Most of my roses didn’t survive last winter’s cold.
    But for the beauties left what can we do?

    This is a wonderful site, and I appreciate being able to write you a note.

    Joyce Koreman
    48304

    • Deborah Silver says

      Dear Joyce, I would read the Vapor Gard label, and see if it is approved for roses. If it is, what could it hurt? You just need to pick a day to mspray when there is no rain, so the film has a chance to dry. Best, Deborah

  4. Starr Foster says

    Wow. Best thing I’ve ever read about boxwood. You are truly an expert who has learned from vast experience, not just books. And is also timely, as I need to rehab a BW hedge. Love the gorgeous photos. Many thanks, Professor Silver!!

  5. Roger Boeve says

    In Virginia, the winter weather is not our primary concern. It is Boxwood Bliglht, a disease for which there is no cure. I’ve removed over 100 boxwoods and many fear that all the old boxwoods on the plantations around Richmond are at risk. What a shame. This disease is moving across the U. S. Sorry to be the bearer of bad news.

    • Deborah Silver says

      Dear Roger, I dread the thought of that blight. I am so hoping that someone will discover a treatment-soon. I am so sorry you have lost so many. Deborah

  6. Sue Brandon says

    Dear Deborah,

    I live along the coast of Rhode Island and we have had trouble with boxwoods due to the cold temperatures as well as boxwood blight. I have found Ilex crenata compacta Hoogendoorn to be an acceptable substitute. It can take hard pruning and in our case, can withstand the cold humid air off the water.
    Good luck,
    Sue

  7. I am a boxwood newbie and just bought 2 small boxwood (winter gem and dwarf english) and would like to grow in containers in Philadelphia, PA area. They are still in their nursery pots, but was planning on moving to large plastic planters and letting them winter next to the house out of the wind. someone mentioned wrapping them in plastic. Now wondering if I should put in garage or basement instead of outside, leave in original pots or go ahead and plant in containers? Another person recommended putting a box over them to keep heat in…help!
    thanks

  8. Debra Lenzen says

    Hi Deborah

    Do you know where I can purchase Vapor Gard? Thanks!

    • Deborah Silver says

      Dear Debra, buy Vapor Gard if you have a lot of boxwood to do. It is only sold by the gallon – Hortmark is a distributor. For small numbers of boxwood, Wilt Stop by Bonide is available in smaller and ready mixed amounts. Garden centers carry it. Best, Deborah

  9. Rachel Kohn says

    I’m reading this advice too late in regard to spraying my boxwood for winter protection. We were considering covering our small boxwood bushes with styrofoam covers as they are right below our roof line and we often need to clear the roof of snow during the winter (Wisconsin) and we don’t want the weight of the snow destroying the bushes. Having them covered can protect them from snow, wind and temperatures but what about winter sunlight? They wouldn’t be the prettiest things, either, but would blend in with the snow as they are white.
    Thanks!
    Rachel

    • Deborah Silver says

      Dear Rachel if you have snow like we do, it would break a piece of styrofoam.If you shovel snow off the roof, you may need sheets of exterior plywood. What does your local nursery recommend? best, Deborah

  10. I appreciated this site very much. I have two nice boxwood shrubs in beautiful large concrete planters. This will be their first winter. I hate having to dig them out. I am going to keep watering as much as possible and cover with burlap and hope for the best in the spring. We do have some bad winters here in the northeast (NY) — any other suggestions? Cannot afford to buy gallon of spray for just 2 shrubs.

  11. Hi, I just bought/rescued the last Winter Gem Boxwood (Buxus microphylla) at a local Home Depot (3.7Gal pot, for $3.00) It appears robust and the top leaves are just turning golden. We just went through a hearty snow and freeze over the last few days (I live in Chicago) and I was wondering if I can care for this inside until spring. I am afraid that at this late time in the year, if I plant it, it will not survive the winter.
    I am a novice so any assistance provided would truly be appreciated. This is truly a beautiful evergreen and I hope to enjoy it for years to come.

    • Deborah Silver says

      Dear Dave, you cannot keep boxwood indoors. If you can get it in the ground (next week you should have milder temps)spray it with an antidessicant like wiltpruf, and burlap it against winter winds. Be sure you water it thoroughly. Good luck, Deborah

  12. Hi Deborah:
    I was admiring your buxus photos and am creating some plant tags for our nursery here in Canada. I was wondering if I am able to use your photos? I would send you proofs before we go to press.
    Looking forward to hearing back from you.
    Regards
    Rob – Pan Am

  13. robert wills says

    what amazing tops for boxwoods! thank you deborah.
    ok my turn to ask a question which is really just a confirmation of all answers above so in our case Deborah, which is three beautiful boxwoods in plastic pots that adorn our pool area, would it be correct to say :
    -water Now liberallly, then, spray them with vapor guard, no need to wrap in burlap, and park them in the unheated cabana for the winter?
    bonus question: dont they need some sunlight during the winter OR are they completely dormant?

    • Deborah Silver says

      Dear Robert, you have a good plan in mind. But if the winter is exceptionally bitter cold,as it was for us several years ago, even the protection of an unheated building was not enough – we lost some. Mostly non-hardy varieties.Their roots were still above ground. I have a few clients who have boxwood in pots for the summer. We plant them in the ground in a protected spot for the winter, soak them thoroughly, and vapor gard them. No, they do not need light for the winter. hope this helps. best, Deborah

      • robert wills says

        thanks deborah! i just dont have it in me to plant these boxwoods for the winter. i will roll the dice in the cabana with them. you have been exceptionally helpful and insightful where others were not, i will let you know how they fare during our mild Canadian winter! Rob

  14. Deborah,
    Amazing pictures and thank you for sharing. I have a quick question and hopefully you can help. I planted several varieties of boxwoods in clay pots early this year and with winter coming on I am clueless as to whether I have to bring them in or not. The pots are old and not important, but I definitely don’t want to lose the plants. I applied an anti-desiccant a few weeks back and live in a zone 6 coastal area in NE Massachusetts. Any thoughts? Thanks in advance.
    Tony

  15. Dear Deborah, I am grateful for your posts and am a huge fan. I live in NW Montana and so want to plant boxwoods throughout the garden part of our 10 Acres. We are in zone 4-5a and do get winter winds and a lot of snow. I tested a couple of plants last year, spraying with wilt stop and planting in the ground. They did not fair well – burned on top. Now I am hesitant and discouraged. Do I have to give up using boxwood or can I do something better to protect them from our deep snow? I can absolutely try the professional vapor guard but am poised to plant a ton of boxwood so don’t want to get them in the ground only to kill them. I appreciate your advice.

    • Deborah Silver says

      Dear Tournesol, I would be afraid to advise you. Snow protects plants from burn-the tops of your boxwood must have been exposed to cold temperatures and winds. You should ask a good nursery person near you which variety you should plant, and how you should protect them. Also the location is important too, take pictures of the place where you want to plant them. Definitely ask about hardier substitutes. good luck, Deborah

  16. I bought 8 boxwood topiaries for a garden wedding this year. They came from Costco. I planted them in larger plastic pots and they have grown beautifully il live in Bloomfield Hills, Mi., a northern suburb of Detroit. They are 3 vertical globes, on a single stem. I don’t know the species. It would be easy to put them in the unheated garage,sprayed with Vapor Gard. The temperature have been so variable in past winters. I worry about that. If I dig them in, I worry about my enormous rodent population. Can they be put in ground in their pots? Or protected by hardware clothe? I don’t think the snow will crush them becaue of their shape. However, they may get buried, which may be good? I’m hoping for advice.

    • Deborah Silver says

      Dear Kari, water them thoroughly, and winter them in your garage. best, Deborah

      • Thanks so much for this! I want to winter MY costco topiaries (my second year for these…had to hunt them down!) Do I water them thoroughly now, place in garage, and leave them alone? or water monthly? any advice is welcome! (i’m in the chicago area) thanks!

        • Deborah Silver says

          Mary, Water them when they need it (i.e., the soil is dry down inside) until the root ball freezes. They put them back out in March – as soon as the weather moderates. Then water again when the root ball thaws. Use your good judgement. best, Deborah

      • also, is vapor guard necessary in a garage? Thanks, mary

        • Deborah Silver says

          Dear Mary, it could not hurt. But maybe wilt pruf would be enough protection, since they will be out of the wind. best, Deborah

  17. Help! I think my beautiful boxwood topiaries are dying this winter. Is this site still active?

  18. Virginia Cromwell says

    Will ‘Green Velvet’ boxwood tolerate hot afternoon south west sun, salt spray, and wind. Winters can get down to freezing for 3 to 4 days, but mostly stay in the medium 30s range.
    Want to use as a hedge to define the edge of a deck.

    • Deborah Silver says

      Dear Virginia, I am flattered that you would ask me, but you need to consult with a horticulturist near you who understands what conditions you face. I am in Michigan-I have no experience with salt spray whatsoever! all the best to you, Deborah

  19. Amy Bautko says

    Hi, we need some major advice! We live in Michigan. We put a pool in and were told by the city that we could not plant anything in the ground behind it due to the water line so…. my husband built a big beautiful planter around the back side of the pool. Our plan was to plant boxwoods in the planter with maybe some grasses or something at the corners to give us some privacy. I went to the nursery yesterday and they told me that nothing will survive the winters out of the ground like this. They said the root ball will freeze. Now we have 100s of dollars and time invested in these planters and don’t know what to do. Is there anything we can plant that will survive Michigan winters? Could the boxwoods survive if we somehow insulated the planters?
    Any advice is helpful! Thank you!

    • Deborah Silver says

      Dear Amy, you need a large container to keep boxwood going in them over the winter-a lot bigger than the root ball of the boxwood. You could line the planter with insulation board before you plant. Or you could take the boxwoods out, and plant them in the ground for the winter. I would definitely spray any container boxwood with vaporgard before the night temps drop below 50 degrees. Growing broad leaved evergreens in containers is not easy.Good luck. I hope this helps, best, Deborah

  20. Karen Schultz says

    Dear Deborah, I have contacted local nurseries here but have gotten mixed ideas about protecting my boxwoods, from digging them up to building a cover with chicken wire or putting plastic pots over them. None of those ideas sounded good to me because of the amount we have planted in many spots all over our yard. Then I came upon your site and the amazing photos and your the knowledge you have regarding boxwoods, so I am hoping you can help. In June and July we redid our landscaping and among other plants, we planted about 30 small boxwood. We have deer and moose here so boxwoods seemed to be the perfect plant. Each plants now is only about 1.5″ round and 1′ tall now. They have plenty of mulch around them now. However we are in Northern Idaho and winter is coming and was told heavy snow weight will damage them. I plan to purchase some vapor guard as you mentioned. You mentioned burlap but wouldn’t the snow still squash them? My husband could build some small wooden 3 sided boxes, if you think that would help. My boxwoods are doing beautifully and I would be heartbroken if I lost them this winter, so any advice you can give would be highly appreciated. Also my 2nd question is, I have yet to start pruning the boxwoods, and they have started to sprout new shoots.. Do I cut those new shoots back before I cover them for the winter with whatever you suggest? Thanks in advance for any advice you can give me, Regards Karen

    • Deborah Silver says

      Dear Karen, do not prune your boxwood until next year. If they are only 1 foot tall, I doubt they would be damaged from snow-the snow would protect them.I am assuming what you planted is root hardy in your zone. The issue is protecting them from winter burn and desiccation.The vaporgard and snow cover will do that. But all this said, I do not garden where you do, and what I say may not apply to your conditions. A local expert is the best source. thanks, Deborah

      • Karen Schultz says

        Thank you so much for your fast reply and suggestions. I just purchased some Wilt Pruf after not being able to find any of the Vapor Gard anywhere in this area. I am hoping it works as good as Vapor Gard. As for covering them, I am glad you don’t feel it necessary. Boxes or burlap would not be attractive and local nursery suggested pots but I know the deer would just keep knocking them off. With your suggestions, I am hoping they do just fine over the winter months. We are already down in the 40’s at night here so winter isn’t far away.. Much regards, Karen

  21. Hi Deborah,
    Do you use the Vapor Gard for cut evergreens that you put in pots?

    • Deborah Silver says

      Dear Clair, Sometimes yes-if the exposure is harsh.I try always to use it on boxwood-as that broad leaf is especially susceptible to dessication.

  22. Hi Deborah, What a fantastic blog! I’m a novice gardener. We have a walled, 15th floor terrace, in NYC with 14 velvet green boxwoods planted in large metal containers since the spring. The plants get no sun in winter and are against a brick guard rail. We can’t move them to a garage (we have none!), nor plant them in the ground and did not insulate them prior to planting. Other than using vapor guard/wilt pruf now, and putting some mulch over the soil, is there anything else we should do to protect them this winter? Any advice would be greatly appreciated!!
    Thanks so much, Ali

  23. Bela Patel says

    Hi Deborah,

    I am looking to find out what the specific name of the boxwoods that are sold in the Detroit area. I was there over the summer and the family member who’s house we visited had the most beautiful boxwoods. I would love to have that exact same variety but have been unable to find it in the Atlanta area. Please help!! Thx!

    • Deborah Silver says

      Dear Bela, there are many types of boxwood sold in this area. The only way to identify a certain kind for sure is to take a spring of it to a nursery, and see if they can tell you the specific name. hope this helps, Deborah

  24. FRANCINE MATHIEU says

    Hello Debra, I live in Canada and I am wondering about boxwood in container over here. Is it feasible, can I bring the containers in for the winter? I would love enjoying them outside in the summer and inside with fairy lights in the winter. Would love your view on the question

    • Deborah Silver says

      Dear Francine, boxwood is a hardy shrub, not a tropical houseplant. It would not tolerate being inside the house for the winter. That said, try one, and see if you can get away with it. best, Deborah

  25. Tom Van Dis says

    I very much appreciated your article Deborah and the other advice you provide through your site. I live in Richland in Southwest lower Michigan, near Kalamazoo. I planted 8 green velvet boxwood plants along the edge of our new patio in June, 2018. The landscape company I bought them from said the were very hardly and there was no need for winter protection. But in February, 2019 while we were away on vacation we had a very cold spell (it was -20 degrees F one night) and they sustained some damage. One is still very damaged but may recover and the other 7 now look fine. Since then, to provide winter protection, I put a 27″ high circle of chicken wire around each plant, covered the chicken wire with burlap and put leaves inside the chicken wire around each plant. Last winter I also used Vapor Gard as you recommended and the plants have done better than ever this spring. The chicken wire/burlap barrier along with Vapor Gard has worked very well but the putting up and taking down the chicken wire, burlap and leaves is a lot of work – especially the leaves. I’d appreciate your advice on two questions:

    1. Do you think it would be OK to not use the leaves in future winters when I put up my chicken wire and burlap? The burlap I use is 10 oz. tight weave and 54″ wide so I drape it over the chicken wire and I have two layers of protection; one layer on the outside of the chicken wire and the other layer on the inside. I fasten the burlap securely to the chicken wire. The space between the wire and the plant is small – around 3-4″ at most. With no leaves it would still fill with snow which provides extra protection from wind but for much of our winters these days there is little or now snow. It seems to me that the two layers of tight weave burlap would provide enough protection from wind but I’d really appreciate your opinion.

    2. It would be even less work if I simply wrapped each plant in burlap without using chicken wire. I would use a double layer of the 10 oz. tight weave burlap and wrap twine around the burlap to hold it securely. I could leave the top open or tie it shut. Do you think the burlap alone would provide enough protection or do you think I should continue to use the chicken wire and burlap as described in my question no. 1 above? If I you think it’s OK to use only burlap should I tie the top shut or leave I open to the air?

    Thanks for your help!

    • Deborah Silver says

      Tom, I am flattered that you think I would know the answers to your questions, but I would only be speculating. I have never burlapped boxwood. But I do soak them with VaporGard when the temps are still above 50 degrees, and it will be dry for a few days. best, Deborah

  26. Vinesh Jagmohan says

    Hi Deborah,

    So I just planted some very young cone shaped boxwoods, hydrangea, Coniferous and a bunch of barberry’s. I live in NJ where winters can be nasty with heavy snow, winds etc. How to best protect these young plants? Seeing so many suggestion. I went ahead and bought burlap role and plastic drop cloth. Can I cover the plants with burlap and then put plastic on top of burlap this way the plastic will not touch the plant but will protect it from snow. I am always concerned with the weight of the snow crushing the young plants.

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