IN THEIR NATIVE HABITATS, Clematis don’t have that post holding up your mailbox to support them, or a piece of wooden trellis. In nature, they scramble and climb through other plants, which offers us a hint of just how versatile and willing they are, and the many ways to use them in the garden.
Linda Beutler is author of three books about clematis, president of the International Clematis Society, and curator of the Rogerson Clematis Garden collection in the Pacific Northwest, just outside Portland, Oregon. Suffice it to say, Linda knows from clematis.
In a recent conversation, Linda shared tips on matching the right clematis to the right support, and what to look for (not flowers!) when buying nursery plants, and why following the traditional rules on pruning without applying some common sense as well isn’t the way to go. Plus: Enter to win Linda’s “The Plant Lover’s Guide to Clematis” by commenting at the very bottom of the page. (That’s Linda, below, in the wild with Clematis spooneri, a close cousin of C. montana.; photo by Ken Woolfenden.)
Read along as you listen to the March 12, 2018 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).
clematis q&a with linda beutler
Q. I was interested to read, I believe you’re the first American president of the International Clematis Society? Is it usually all Brits, or what? [Laughter.]
A. We do have a lot of British members. Lots of German members. We’ve had presidents from Sweden and Poland, and we have lots of members in Japan, where clematis are quite widely bred. So yes, we’re pretty far-flung.
Q. Truly international.
A. You bet.
Q. Well, congratulations on being the president. And the collection that you curate at the Rogerson Clematis collection tell us a little bit about that, how big it is and what it’s like.
A. I was just messing around in the accessions records yesterday. We have 1,802 plants, and 789 different varieties and species of clematis.
Q. That’s a lot. Did you know that that’s a lot? That’s a lot. [Laughter. Above, part of the collection at Rogerson.]
A. Yes, it’s a lot. It does sound like a lot, but when you consider that there are something like 60,000 different varieties of daylilies in the trade available from year to year, we’re just pikers. We’re just getting started.
Q. Well, on the other hand, we could look at it that the clematis people are more discerning, couldn’t we?
A. I hope so.
Q. That you’ve been more discerning in naming things that are truly distinctive and different from one another. That’s how I’m going to look at it. [Laughter.]
A. Yes, I think we have a lot of breeders who are not always trying to reinvent the wheel.
Q. Right. So now at Rogerson, is it a garden? I mean you just talked about the accession records and that it’s this massive collection. What is it when I come to it?
A. The place where we’re located is called Luscher Farm, and it’s a decommissioned dairy farm, that the city of Lake Oswego bought. It’s part of their parks and recreation system, and we lease two acres from them. We have our office there. Part of our garden wraps around an old farmhouse that was built in 1900, and there’s a barn, a big wonderful barn, that is our backdrop. Then we have a series of themed gardens.
We have a front bank that’s very hot where the clematis that like it really hot are. People hear, “Feet in the shade, head in the sun.” And that’s true, mostly. But like all generalizations, there are exceptions.
So we have places for hot things, we have a place for Brewster Rogerson‘s favorites. Sometimes the plants are divided up geographically. Some plants that all like sort of the same climate are put together, even though we’re not that climate. And we have troughs, we have clematis in sort of elevated rock gardens where they have really good drainage when they need it.
And for the most part, the clematis are grown with companion plants, because we want to encourage people to add clematis to their gardens. We’re leading by example.
Q. There’s inspiration, then—ideas as well as just the collection, that we could comb through and say check things off the list, so to speak.
Q. I learned in your most recent book, “The Plant Lovers Guide to Clematis,” which in the name of full disclosure, I’ll say is published by one of our program sponsors, Timber Press … I learned what your favorite clematis is, which is no mean feat having a favorite, because as you just said, there are a lot of clematis to choose from. I learned that yours and mine are the same. Now how weird is that, since we don’t know each other?
A. Oh, that’s great.
Q. Is it ‘Venosa Violacea’ [above]? Is that how we say it? How do we say it?
A. Right, yes.
Q. It’s the striped one. [Laughter.]
A. That’s exactly right. Yes, you know before I became curator, long, long ago when I first started collecting clematis myself, I saw a picture of that plant, and I thought, “Nothing could be that beautiful.” And then I finally got it, and it’s been my favorite all along, all these years. But when I’m at the clematis garden as the curator, I try not to have favorites.
Q. O.K., good. You’re open-minded, and you’re fair to all your charges. O.K..
A. I try to be.
Q. Yes. Well I have it when you walk into my garden, it’s the first plant on your left as you enter at the top of the driveway, and come into the actual garden. It’s growing, as it has for many, many years, through a very, very old, like a 30-year-old Corylopsis spicata, spike winter hazel.
A. Oh, nice.
Q. And then the winter hazel is probably 20, 25 feet across, and maybe eight feet tall and gnarly and crazy, with wacky arms. And then this thing is like scrambling through it, and it’s fun, and it’s just a fun plant.
So speaking of combining, I saw on the Rogerson Clematis Collection website about you and the talks you give, and that you give one called “Shall We Dance? Clematis Make Great Partners.” [Laughter.]
A. That’s a brand new talk that actually I’m still putting together. I’m going to give it in April for the Northwest Horticultural Society up in Seattle. They wanted me to do something new.
I have a real passion for combining these plants. I just love it. It’s so much fun to place these plants in the garden, and to think about combining them both with color and chronologically. You know, when are they going to bloom? What are their partners going to be? Or am I going to do something like you’ve done; Corylopsis spicata is beautiful. In fact, this time of year it’s just coming into its own. And the clematis won’t be in bloom for another two or three months, at least.
Q. Good point, good point. Yes.
A. So you’re using the clematis to give you color where there will not be color in the summer.
Q. Right. Right. And I do the same-in-reverse thing with my … I have a lot of Ilex verticillata, the native winterberry of the East, and those look great in fruit in the fall and early winter, until all the birds eat them. But I have clematis through a lot of them. And I can’t say the name of this one, chiisanensis ‘Lemon Bells’ [above]? I know the cultivar name. Now how do you say the species of that?
A. Well, actually, if we want to be right up to the minute, it’s now Clematis koreana var. carunculosa ‘Lemon Bells.’
Q. Oh, forget about it. [Laughter.] Koreana sounds like it comes from Asia to me.
A. Sorry, I had to, in the interest of full disclosure, clematis are as heir to the whimsies of the taxonomists as anybody else.
Q. Right, right. So ‘Lemon Bells’ is a little lemon yellow bells, and so they do their thing.
A. Let’s just call it ‘Lemon Bells.’
Q. So they do their thing earlier, and then I have the fruit of the ilex later, and there you go, that’s again like what you’re saying. So give us some other sort of sneak-peak ideas, maybe starting from the lower level up to the higher levels of some of the things that might be in this “Shall We Dance” kind of a talk, some other examples that we can use in our yard.
A. Well, a lot of garden designers think of the garden in layers, starting with sort of the ground cover layer and then your herbaceous perennials and shorter shrubs, and then you get up into the taller shrubs and the trees. That’s another way to approach adding clematis to the garden. At the ground level, you’ve got the herbaceous perennial clematis. There are such things. There are clematis that don’t climb.
Q. Love them.
A. And the other great thing about them is that we have a lot of herbaceous perennials that we use in our garden that will re-bloom. The herbaceous perennial clematis are really good re-bloomers, if you keep them deadheaded. Or you can just go out in the middle of the summer, chop them off at the ground, and they’ll be re-blooming by the time you get into September. So anybody that’s got a long growing season should be starting at the ground level with the herbaceous perennial clematis.
Some of those are a little short, erect plants. Some of them tend to be a little floppier, because they’ve taken these herbaceous perennials and crossed them with the vines. But the gene for not climbing is very dominant, so you end up with a big, floppy herbaceous perennial.
But those are great to go into your hydrangeas, and your roses, and because they don’t cling, they don’t hang on, it’s really easy to get under your shrubs. You cut these guys off as soon as they’re dormant, and you can just pull the foliage out of the shrub without having to prune the shrub or breaking up the shrubs.
And then Raymond Evison over on the Island of Guernsey has done a lot of breeding with clematis that are actually vines but don’t get very tall. So that’s another way to get clematis into the mid-zone. And then you can use your higher ones, taller clematis, to get into trees and so forth.
Q. So for instance, if we’re talking about making these good match ups, we wouldn’t want to take a sort of really, I would say rampant, but that maybe is a negative word, but like a Clematis montana that grows a lot, I think, you wouldn’t put that on a small shrub like I was talking about before, correct? You wouldn’t overwhelm it.
A. Right. You have to pair them—to do a little research and read your plant tags and see what the maximum height is. Generally, it’s a truism that the clematis is going to get to its mature size before any shrub or small tree you’re going to put it in. With the montanas, I really try to get people to use them like a festoon on balconies, that sort of thing, where they’re actually supported by something that isn’t living.
Q. A pergola. Yes. [Above, C. montana ‘Brewster’ on an arbor at Rogerson.]
A. But Clematis montana can get really heavy, and here in the Pacific Northwest and the Maritime Northwest, people love the Clematis armandii, the evergreen clematis that flower in March. Even those, they get huge. And so in the international clematis world, we’re really thinking right now and having a lot of conversations and meetings about how we talk about pruning to people who don’t know clematis really well.
Q. So we’re going to get to that in a minute, because I know that’s one of the things you have to enlighten us about. But before we prune them I want to just double back to the non-vining ones. I have say like Clematis recta, and Clematis recta ‘Purpurea,’ I think it’s a named one like ‘Lime Close’ or something.
Q. So I think of those as non-vining. Is that what you’re talking about? Give us a couple of other examples of those so people can-
A. Those are great examples. There are a couple of really popular cultivars, there’s ‘Arabella’…
A. … that has a real sky blue flower. And she’s a cross between Clematis integrifolia, which is a charming little northern Asia, northern Europe herbaceous perennial plant, has a little four-petaled bell, basically shades of blue. There are also some other variations in the wild that have been used in cultivation. And it only gets, on average, about 18 inches tall. And it’s the real founding parent for ‘Arabella,’ her sister ‘Miranda,’ and Clematis durandii, which is another really popular one. Those are names that people are going to see.
Q. O.K. Thank you.
A. Clematis recta is also native to eastern Europe. And if you look at where these plants are native to it’ll tell you what their hardiness is.
Q. Right. Well I’m a Zone 5 and I’ve been growing that for eons and eons. I have numbers of plants and it’s gotten to be quite a lusty creature, it’s massive. But I love the purple one. Yes, I love the purple foliage of the purple one [above].
A. Yes. The ‘Purpurea’ called ‘Lime Close’ is not lime green, it’s named for the nursery where it was discovered called Lime Close.
A. And it comes out of the ground as deep chocolatey-purple color.
Q. It’s unreal. It’s unreal.
A. And if you have a long enough growing season that when it’s done flowering you can cut it back to the ground. The new growth is purple every time it comes out of the ground.
Q. I am so grateful for that tip, because I’ve had it probably 20 years and I didn’t know that. Isn’t that crazy?
A. Yes. Every time it comes back, it’s that dark purple color again. And then you’ve probably noticed that it goes towards green as it gets towards flowering.
A. And then once it’s done flowering, say about Bastille Day or so, middle of July, you can cut it right back to the ground, and then as you go into the autumn it’ll come back up, it’ll be dark purple again and it will rebloom but it won’t get as tall.
Q. Oh my goodness, I’m so excited. I’m going to get like a triple-dip out of this one plant that I’ve known only one way for all these years. So excellent.
A. There you go.
Q. So, other it was sort of in that middle height, because I think that’s what a lot of us have in our gardens. We have a lot of shrubs more than we want to have something to grow up a giant tree. What are some of the intermediate ones that you want to make us look for?
A. That’s where a lot of people use the large-flowered hybrids. [Above: lavender ‘Minister’ and ‘Fond Memories.’]
A. And some of the large-flowered hybrids can be sort of rangy, meaning they want to put on 6 or 8 feet of growth before they even think about flowering. And those are actually kind of nice to put into shrubs because you don’t notice they’re there until they work their way to the surface. And she’s passed away now, but a local garden writer named Dulcy Mahar, had the most wonderful combination in her garden of a really reddish-pink ‘Glowing Embers’ hydrangea with a wonderful stalwart mid-century clematis called ‘Rouge Cardinal,’ or ‘Red Cardinal’ [below] sometimes you’ll see it.
But it was just this lovely combination because the pink was really rich, and then the clematis was this really velvet- textured plant when it was in bloom. So you had the mopheads with the clematis, so you can play with texture as well as color. And that’s a clematis that really wants to go; it’s a plant that it’s hard for nurseries to sell because nurseries are timid about cutting it back to keep it under control in the nursery because they know that they’ve got to let it go some to bloom.
Q. Right, because vine nurseries can get to be a messy place if millions of vines…[laughter]…
A. I’m actually preparing some talks to give at symposia at our retail-nursery trade shows, to talk about really what they can best do to be selling customers the best possible clematis plant. And it isn’t always let the thing bloom. Not every flower bud is sacred, and the root system is a whole lot more important, and the number of shoots is more important than is it in bloom when you buy it.
Q. So speaking about maybe sometimes when things need a haircut, let’s talk about pruning—you alluded to it before, and I said, “Wait a minute,” because I wanted more good clematis names first. We’ve all been taught the Type 1, Type 2, Type 3: according to when the plants bloom the clematis are divided up according to their bloom time, and from there we’re supposed to extrapolate how and when to prune them.
And that sort of works, but I understand from you that there’s some evolving thinking about that. Can you clue us in a little bit?
A. Right. The first thing that any gardener needs to worry about with their clematis is pruning for the health of the plant.
A. And if you have just one or two stems coming out of the ground and this whole great mass of top growth you have a lot riding on those few little stems. So it really is long-term the best thing to get rid of those big snarls when the plant is dormant.
And I’m always encouraging people and especially whenever we have new volunteers at the garden: Don’t be timid if you’re going to prune.
And some people deadhead to get the clematis back into bloom more quickly. And I always say, “You know, that’s a great time when you’re deadheading to also be sculpting, to be thinking about the plant has flowered in May or June, I’m going to go out and take the flowers off of it, and take another foot or 2 or 3 off of the plant at that point, and don’t be shy about pruning.” Because really the only way to kill a clematis by pruning is if you just prune so often that it never gets to leaf out.
Q. Right. No photosynthesis means a dead plant eventually.
A. Right. But as far as, “Well, do I prune it in the fall or do I prune it in late winter?” There’s really not much difference because pruning in and of itself in the winter when the nights are cold and the days are short, clematis aren’t stupid and they know they’re not supposed to grow then. So, really, as soon as they go dormant in the autumn, if you’ve got a lot of vines that you want to take back and you don’t want to look at it all winter, cut it back.
And with the herbaceous perennial forms, of course, that woody growth might seem pretty stout but it’s not going to come back. The new shoots are going to come from the base. So you can go ahead; a lot of these plants you can clean up in the fall.
But I think the traditional pruning group that has always bugged me the most is Group 1, because people see that and they think it means these are clematis that shouldn’t be pruned. And there are no clematis that shouldn’t be pruned at some point. So you have to think about what you want the clematis to do. And, for instance, the evergreen Clematis, the armandii and there’s ‘Snowdrift’ and ‘Apple Blossom’ [below]. And you probably can’t grow them, I would assume you couldn’t.
Q. No, I don’t think so.
A. Yes. But on the coast, on either coast and along the South, they’re grown quite a lot. And they get heavy, and the canes get really thick and woody, and you have to prune it some, unless you’ve got a really stout balcony that you’re growing this thing onto, you really should be pruning it back, and you can prune it back quite hard if you do it when it’s done blooming. And then it has the whole growing season to recovery, because this is a plant that flowers in March and April, then you cut it back as much as you need to, and it’s got all summer and fall to recovery. And so, it’s a timing thing.
But still, I wouldn’t ever say to somebody, “Never prune it.”
A. Because that’s a recipe for disaster.
Q. So we want to apply … the groups and everything can be informative, but we don’t want to follow a rigid system at the expense of having some, as you say, some creature with two spindly, crazy stems that are 6 feet tall and nothing else going on.
Q. So we want to also look at the structure, the armature that’s being created for this plant to thrive, yes? [Clematis ‘Freda’ scrambles up a chainlink gate, above.]
A. Exactly. So, when people go to a nursery to buy clematis they should be looking at the base of the plant, they should see a few roots coming out the drainage hole, and they should see at least two shoots, and hopefully more.
And then, another piece of advice that I have for people is when you go to plant your clematis, if it’s a really wild tangle that the nursery has just let go then it really should be cut back a little bit. You don’t want to take all the leaves off of it when you go to plant it, but if it’s in a gallon size pot with a hardwood stake that’s actually affixed to the pot, which is, I think, what people usually see, cut the plant back to the top of that post. It reduces transplant shock, it makes it easier to get it in and out of the pot and into the ground, and it just encourages the plant to root out faster and to put up more shoots more quickly.
Q. Makes sense.
A. So I always recommend a little bit of pruning or a lot, depending on the condition of the plant when you buy it, but when it goes in the ground.
learn more about rogerson clematis garden
more clematis interviews
- Extending the clematis season
- Pruning according to the traditional group system
- Other clematis I grow (plus slideshow)
enter to win ‘the plant lover’s guide to clematis’
TIMBER PRESS HAS SHARED an extra copy of Linda Beutler’s “The Plant Lover’s Guide to Clematis” with me, to in turn share with one lucky reader. All you have to do to enter to win is comment in the box at the very bottom of the page, answering this question:
Are there any clematis scrambling up any kind of supports–living or architectural–at your garden? Any favorites you want to tell us about?
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MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its ninth year in March 2018. In 2016, the show won three silver medals for excellence from the Garden Writers Association. It’s produced at Robin Hood Radio, the smallest NPR station in the nation. Listen locally in the Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) Mondays at 8:30 AM Eastern, rerun at 8:30 Saturdays. Or play the March 12, 2018 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).