SHRUBS: I think of them as the sort of human-sized plants, and they definitely are the backbone of the garden. Ken Druse and I each have a lot of different shrubs, and I asked him the other day, “If you could only have three, which ones would they be?” Well, that’s our topic today—desert island shrubs.
You all know Ken, old friend, great gardener, and author and photographer of 20 award-winning garden books. He helped me try to narrow down our list of must-have shrubs to the real standouts, and explain why which ones made the cut. (Hydrangea quercifolia ‘Snowflake,’ above, an oakleaf hydrangea, is on his list.)
Plus: Enter to win a copy of Ken’s book “The New Shade Garden” by commenting in the box at the very bottom of the page.
Read along as you listen to the November 9, 2020 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on Apple Podcasts (iTunes) or Spotify or Stitcher (and browse my archive of podcasts here).
desert island shrubs, with ken druse
Margaret: I know you’ll never get it to three, Ken.
Ken: Well, it’s funny you said that, because when we first started talking about it, you said one. And both of us thought, “We can’t pick one.” Can we even pick three? We’ll try.
Margaret: You and I, in our lives are at what another expert friend says is “the shrub season of our lives,” which is sort of rather than crawling around dealing with lots of fussy, high-maintenance perennials, it’s kind of great to have some big fillers, like mature shrubs, to do a lot of showing off and yet not ask a lot of us. So, where do we begin? What’s a shrub, I guess?
Ken: Well, a shrub is a multi-stemmed plant, a woody plant, and I guess that sort of describes it. A tree would have one trunk, one stem. Herbaceous plants die down to the ground, and they have soft tissues. And a shrub is a woody plant that is bushy. Bush—I don’t like that word for describing a shrub, but a shrub can be bushy.
Ken: How’s that?
Margaret: O.K. And we should say before we start naming our desert island shrubs that we didn’t include conifers because, really, that’s a whole other conversation—so many shapes and colors and textures among those.
So, do you remember your first shrub? And is it still there and is it a favorite, or it didn’t make the list?
Ken: [Laughter.] Well, I get to pick three, right?
Margaret: O.K. You want me to tell you my first?
Ken: Well, you said conifers and I’m not going to talk about conifers, but I might… One of my favorite shrubs is evergreen. Well, it’s called a broadleaf evergreen, and it’s a Buxus; it’s a kind of boxwood. I have too many of them, and it’s Buxus sempervirens ‘Graham Blandy’ [above, at Ken’s].
Ken: And it is one of the most columnar plants I’ve ever seen, really, but it’s a shrub. I have some that are 7 feet tall and 15 inches wide, if you can imagine that.
Ken: So they’re like punctuation marks, they’re like exclamation marks, in the garden. And as I said, I have too many because when I first thought… I always wanted them, and then a nursery not too far from here had a whole lot of them and nobody bought them, and the price kept going lower and lower and lower. I may have 20 of them when they were $8 a piece.
Margaret: [Laughter.] Wow. That’s a lot of exclamations. [More from Ken on using columnar plants.]
Ken: A long time. I know. And I also keep moving them. I just moved three.
Margaret: Oh boy. Sun? They want sun?
Ken: I’m sure they would love sun but I have all my boxwoods… Well, I don’t have any full sun. But I have some of my boxwoods in quite a bit of shade and they stay columnar. Sometimes I tie them up because the snow might split them a little bit, or you know splay them; they don’t break.
Ken: But I do tie the ones that are floppy up for the winter. But I love it. If you can picture it. It’s just-
Margaret: So the boxwood called ‘Graham Blandy.’ Columnar.
Margaret: O.K., I don’t actually have any evergreen things at all on my list, whether broad-leaved or coniferous. And I was thinking when we started this conversation the other day on the phone that my first shrub passion was the genus Viburnum. And back in the day we had a lot of Asian viburnums like the doublefile and so forth that turned out to be kind of invasive in a lot of areas of the country, so I don’t grow those anymore.
But the thing I have the most of—you said you have a lot of ‘Graham Blandy’—is winterberry holly, speaking of fruited things. And I don’t know what came over me, I mean, it was the birds that came over me early on here in this rural place, having been grown up in the city.
Coming here and meeting all the birds and knowing that, learning that, some of them liked fruit—and that the native hollies were one of the ways to fuel the migration and the wintertime.
And I planted about 45 or 50 of them in three very large groups in different directions toward the perimeter of the property but in different directions where I can see them from key windows in the house at a distance in the winter. All different varieties—big ones, small ones. I got a lot of fruit. [Laughter.] And the birds like me very much.
And yeah, so waxwings and robins, I can hunt flocks of 100 or whatever at a time will come in, right around now, November-ish, and again, to pick over it at the first snowfall, and so forth and they’ll strip them all pretty early on.
But one trick with the winterberry hollies if you want some that will last longer for your visual interests, the non-red varieties—the birds leave them longer. They’re not as interested in them. [Above, Ilex verticillata ‘Winter Gold.’]
Ken: I am [laughter].
Margaret: Yeah, right, but the yellowish orange ones and so forth-
Ken: Right, I love those.
Margaret: The lighter-colored ones. Yeah.
Ken: And the winterberry has really nice bark, too. A lot of people don’t limb them up or cut the bottom branches off, but they have beautiful gray bark, I think.
Margaret: Yes. Yes. So that would be one of mine. What’s one of yours?
Ken: Well, a long time ago you told me that birds come for different times of the year for different kinds of fruit. And I guess the winterberry probably is starchy maybe or something because it’s-
Margaret: The winterberry is actually high in lipids or oils, so it’s calorie-rich, and very sustaining. Yes.
Ken: But it’s taken kind of late, compared to the juicy, sugary fruits.
Margaret: Correct. Yes.
Ken: Well, another one of my favorites has fruit that I don’t think the birds are too interested in, but it’s the… Used to be called Poncirus and now it’s called Citrus, Citrus trifoliata. And I have a contorted version called ‘Flying Dragon.’ And it’s beautiful as a shrub, and it’s magnificent when it’s covered with real oranges even though I’m in Zone 6a. And they’re a little bigger than golf balls and they’re fuzzy and kind of gorgeous yellow color, like the sunshine [above, at Ken’s].
And it’s just a beautiful plant. Very easy. When I first got this plant everything I read about it said it was Zone 7 and it wouldn’t live. And I saw one on Long Island and I got some fruits and I grew one from fruit, from a seed, because the fruits are not really… I guess they’re edible, but you wouldn’t want to eat them because they’re really sour.
And one fruit might have 30 seeds in it, but I’ve grown one here from seed that I’ve probably had for about 30 years and I was coddling it indoors. Then I got a ‘Flying Dragon,’ I planted outside and it’s been down to minus 10 degrees without missing a beat. So now I have two, I have some species I grew from seed probably 30 years ago, and I prune that, and the ‘Flying Dragon’ is all wavy and contorted and it has thorns.
Margaret: Thorny, yes.
Ken: And on the ‘Flying Dragon’ the thorns are hooked, so I always thought when I had the house in Brooklyn, I actually did this. When I had the house in Brooklyn I grew mine for the summer and the spring outside as a sort of a way to stop burglars. [Laughter.]
Margaret: It’s barbed wire. It’s Ken’s version of botanical barbed wire.
Ken: Of course. Well, we try to do that with all plants, double-duty.
Margaret: Yeah. So I almost said Poncirus, I have no idea; but you’re saying it’s in the genus Citrus now. And the species again is?
Margaret: O.K., good. So that’s one I’ve never even tried. If I have the most winterberries, the thing I have the second most of probably are Aesculus parviflora, the bottlebrush buckeye, which is a whopper of a plant, a kind of colonizing suckering thing. [In fall color in background, above.]
Ken: Behemoth. [Laughter.]
Margaret: And it’s a Southeastern these days, in modern history it’s Southeastern and it’s native to the Southeast, but before the last glaciers for all we know it was up North, too, because it’s bone-hardy even in the Midwest and Northeast.
The bottlebrush buckeye. The buckeyes are not, they look like chestnuts, they’re poisonous. You don’t eat them, but the squirrels run off with them like mad.
And this guy is a whopper: Aesculus parviflora. I have the straight species, which I’ve had about 30 years. It’s probably 15 high, and incredible fall color, gorgeous flowers that are many little tiny tubular flowers on a wand, on a big wand—kind of a creamy off-white color with a dark sort of orange-y interior. The butterflies love them, the pollinators love them, and I’ve even had Baltimore orioles, who are nectivorous, they’re nectar-seeking birds, drink at the little flowers, these beautiful flowers right at the 4th of July it blooms [below].
So it’s an interesting shrub, not a spring bloomer, it’s this July bloomer and wildly fantastic yellow fall color. And then I have the later variety which blooms like two weeks later, ‘Rogers Strain.’ So I have sort of an extended season. And now—and I think only Song Sparrow Farm and Nursery in the Midwest, I think they’re the only ones who had this—but from Dawes Arboretum in Ohio there’s a dwarf called Dawes Dwarf, for people who don’t have a big garden. So that would be probably my most… I’m looking out the window right now at massive blaze of yellow. [Update: Song Sparrow says they are winding down retail sales after 2020.]
Ken: It’s like bigger than a school bus.
Margaret: Oh, I’m checking…they’re a big circle. It forms like a hummock, a mound, a giant 15-foot… I just adore them, and it’ll grow in the shade.
Ken: Oh! Well, you really need space for that guy. I think the flowers are fragrant, too, aren’t they?
Margaret: Yes. They’re a little bit sweet. I don’t notice the fragrance from a distance, but as I said the insects really love it. The skippers, the butterflies called skippers, they love it especially. So it’s quite the attraction for me and for the wildlife. So, what’s your next desert island shrub? [Laughter.]
Ken: Well, my next desert island shrub is also native to the Southeast. I imagine you could grow it. I don’t know exactly the limit of hardiness for Hydrangea quercifolia, the oakleaf hydrangea.
Margaret: Oh, sure.
Ken: I love those plants. And some years they have magnificent fall colors, some years not as good, some years are sort of reddish, but some years they’re burgundy; incredible. But I don’t grow it for the foliage color, even though it’s great. I grow it for the flowers, and there’s one that’s very popular that has too many flowers.
I think of it sort of as the Barbra Streisand of oakleaf hydrangeas because it’s zaftig, if you know what that is. But I like the one called ‘Snowflake,’ which has, I guess you’d say, they’re double or sort of hose-in-hose. So it has a flower, and then a flower in the center of the flower, and the flower in the center of that flower, so that it keeps going, and keeps going. And then the flowers turn pink on these huge panicles, and then green. And when they’re green and ripe you can cut them and bring them inside.
They’ll turn brown and they’ll last as long as you can tolerate the dust on the mantle, and then just pick new ones and put them there. But it’s really beautiful, and I know we’re going to have at least one photograph of our favorite shrubs on the website. But that’s for years, that’s a favorite. And it’s also really easy to layer to ground layer. Is it?
Margaret: So to make a new shrub by bruising a branch, and laying it down on the soil you mean?
Ken: Right. And I cover it with a rock, usually. Yeah.
Margaret: So it holds the little knife cut, so to speak, the little peel in the bark is held next to the soil and it’ll root?
Ken: Yep. And then you just forget it for about 12 months and then dig it up and give it to a friend.
Margaret: I’m very good at forgetting things. Is that an advantage in this propagation thing? [Laughter.]
Ken: I think that’s an advantage, you can’t imagine. Otherwise, you’re standing there tapping your foot waiting 12 months.
Margaret: You said two things about that oakleaf hydrangea ‘Snowflake’ [flower detail above]. You said, hose-in-hose, which makes me think—if people don’t know what that is, it’s almost there’s two flowers, one slightly smaller tucked inside each other, a cup with a smaller cup in it. And you hear that a lot of times, if people want to look it up and see examples, about primulas. There are some great old-style primulas primroses that are hose-in-hose, which I adored years ago.
The other thing is you said dusty with dried flower arrangements on the mantel piece.
Margaret: You terrible housekeeper, you. So my friend, Jenny, the flower farmer of Tiny Hearts Farm near me, she says that you just put your on low and on cool your hairdryer, take it outside and just hair-dry them. And she said it’s fabulous, it cleans them off completely. So, FYI. [More on dried flowers with Tiny Hearts Farm owner Jenny Elliott.]
Ken: I clean it with sometimes with canned air or even a straw. But, really, after a year just pick new ones, right?
Margaret: Yeah, yeah. But all I’m saying is if you, if it’s looking a little funky by January or February and you want to keep it longer.
Ken: So we pick so many of the Hydrangea arborescens, too. They’re just so beautiful.
Margaret: Yeah. So I wanted to put in a plug for shrubby or twig, willows and dogwoods, the genus Salix and the genus Cornus, while some of the Cornus have been changed to another genus probably, but whatever, I think dogwood is Cornus. My favorite willow is the rosemary willow, Salix elaeagnos, and has linear blue-gray—they’re almost like giant needles [above]. They look like giant needles from a blue conifer, but they’re not needles; it’s deciduous.
I got this as a little rooted cutting probably 30 years ago. And even when super-expert people come to garden tours here, they ask me what this thing is because no one’s ever seen it grown into almost a tree size. It’s like a small tree at this point because it’s so old, and I’ve never had it back.
With the twig willows and twig dogwoods, usually we cut them back every couple or few years to enjoy the twig color, if they have colorful twigs, and this one doesn’t really have that quality. It’s more for the foliage in the warm season that we grow it. So Salix elaeagnos: I couldn’t live without that one, I just adore it.
And the twig dogwoods in the winter, I’m in a cold-winter, a long-winter area and boy, the red and the gold twigs are just such a treat. My favorites are probably the dogwoods Cornus sericea ‘Sunshine,’ with the yellow leaves in the spring [below, in fruit], and the variegated gold-twig one called ‘Silver and Gold.’ So yeah, I have lots and lots and of twig dogwoods and twig willows all around, especially in some of the looser wilder places. And the ones that are the best wildlife value—those are native shrubs—are all of those are the ones with the plain green leaves, not the variegated or the gold or the purple use because the insects can’t use them as a host plant as effectively.
So, if you’re going to… I mean, I have the showy ones, one-sies of the showy ones, right near the house, the variegated one and so forth, and the gold-leaf one. But in the outer areas, I have multiples of the plain green-leaf one with a lot of insect interactions and bird interaction—white fruits, the twig dogwoods have white fruits.
Ken: Yeah. We’ve been talking about things that got their names changed and that Salix used to be, I think rosmarinifolia.
Margaret: And it may still be for all Margaret knows, because she can’t keep up. [Laughter.]
Ken: No, no. You’re right, because that one I thought, why change that name? It was a perfect name, rosemary foliage. We tried to leave it to three and now you made me think of the Arctic willow, Salix purpurea ‘Nana.’ Oh my gosh, is that a great shrub with bluish foliage? And I do cut that back every spring and it just makes a lovely mound, similar in a way to the rosemary willow, only the leaves are much smaller.
Margaret: Much more diminutive.
Ken: Yeah, and it’s so useful as a shrub, and also deciduous. Wow, you got a favorite lilac? I don’t know how much time we have. [Laughter.]
Margaret: Well, we have a couple more minutes. But, yeah. And, lilacs they’re one-season plants. Well, two week plants, right? I mean, don’t put them by your front walk. I love, and I don’t know how to pronounce it. It was named for a battlefield, world war battlefield in France, ‘Agincourt Beauty.’ I love that one. It is a beauty: dark purple, a favorite. What about you?
Ken: ‘President Lincoln.’ I think it’s the bluest-
Margaret: Oh, blue. Oh, O.K.
Ken: … of the lilacs. And unfortunately it’s lanky, like its namesake. So it’s kind of tall. I have it planted by a second floor, second story window because it’s very tall and skinny. And if you want to pick the flowers you have to lean out to window or get a ladder [laughter] because they’re at the top, but they’re of course they’re all great cut, and I wish they lasted longer, 12 months would be nice. But the smell is great. I think it’s a little early, and these are Syringa vulgaris, right? This is the-
Margaret: Yes, those two are. I also have the hyacinthifloras, which are really nice and more mounded kind of shrubs, some of the white ones [like Mt. Baker’], and so forth. So in the last couple of few minutes tell us, do you have some real oddball to share, because you do have a lot of… Unique is an overused word, but you have a lot of unique plants. [Laughter.]
Ken: I do have a lot of unique plants, and I can’t think of an oddball now because I’ve already named a couple.
Margaret: I know one of yours that I’m always fascinated to see.
Ken: Oh what?
Margaret: That Gingko, that strange Gingko.
Ken: Oh, that is odd. [Laughter.]
Margaret: So tell us, because that’s a shrub, but Ginkgo I think of as a tree, and yours is not a tree [above].
Ken: And ginkgos are very easy to prune and I have to admit I do prune it. But it has multi-stems, and it’s called ‘Todd’s Broom’ [or ‘Todd’s Dwarf’]. If you look online you’ll see a lot of sort of dwarf gingkos that actually have started this way. A broom is a mutation that appears on another plant, and then they can propagate it and it keeps the characteristics of the mutation—in this case kind of tubular leaves, and it’s very stocky. But I do prune it, keep it in bounds, but it’s shrub-like, it’s stocky, it’s about I’d say 6 feet across and 5 feet tall. And it has wonderful yellow fall color that’s just coming on now, interestingly enough, two weeks later than my regular ginkgos. Oh, that is a weird one.
But you were asking me these questions and I thought of my favorite rose. A rose as a shrub, too. Just want to point that out. [Laughter.]
Margaret: Yes. And mine is the blue-leaf Rosa rubrifolia, or whatever we want to call it. Yeah. What’s yours?
Ken: Well, I have a very old rose, and it took me a long time to find out what it was because I didn’t know and it’s called ‘Petite de Hollande.’ It’s an old, very old rose, the kind that was used in perfume, but it has a small flower and the fragrance is beyond description. Lovely little pink flowers just once a year. It’s pest-free and disease-free. It’s from actually from the 1700s. So it’s a very old rose.
I think that a couple of those great old rose heirloom rose-sellers have it. I know that Austin Roses sells it in great Britain, which doesn’t do us much good, but it’s just a wonderful plant. I propagated it and now I have in two places because if I lost them I’d be heart broken.
Margaret: Right, ‘Petite de Hollande’ or something. O.K.
Ken: Right. Exactly.
Margaret: So I’m thinking that, obviously we could go on and on and on, and I’m afraid to even go outside today and see all the shrubs I didn’t shout out and they’re going to yell at me. [Laughter.] So for now-
Ken: Well, we ran out of time.
Margaret: Yeah. Yeah, yeah. But let’s do desert island fill-in-the-blank. Let’s do desert island trees one month, and let’s do some desert island…
Ken: Oh my god. [Laughter.]
Margaret: Because seriously I’m learning about some new things from you, and that would be fun. So, yeah. What do you think?
Ken: Well, I think that’s great. I think maybe we shouldn’t talk about the number, we should just talk about them until we run out of time.
Margaret: Well, I had to try to restrain us in advance, even though I knew it was-
Ken: Yeah, right. Well, we started with “What’s your favorite?” and then it went to “What’s your three favorites?”
Margaret: I know. I know. All right. Well, thank you, thank you, thank you.
Ken: I love you all. [Laughter.]
Margaret: All right. I’ll talk to you later. O.K.
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MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its 11th year in March 2020. 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 November 9, 2020 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes/Apple Podcasts or Spotify or Stitcher (and browse my archive of podcasts here).