MAYBE YOU’RE LOOKING for fun new annual flowers for this year’s garden, fresh ideas for adding seasonal color to pots and beds. Whenever I visit a public garden, I see gorgeous plants I don’t recognize and also ones I do sort of, but in some extra-special variety I haven’t seen before, like a gold-leaf Gomphrena or some new shade of black-eyed Susan vine, or perennial sedges used as filler in pots. So how does the horticulturist behind such designs find all these goodies and know how to use them so boldly?

I decided to invite one to the show to find out. Here to help is Head Gardener Timothy Tilghman, of Untermyer Gardens Conservancy in Yonkers, New York, an ambitious restoration of a historic landscape that he’s been undertaking with his team since 2011 and gaining lots of praise in the press and from visitors. (That’s Timothy watering the greenhouse flats of annuals, below.)

Read along as you listen to the Feb. 25, 2019 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Spotify
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hot annuals, with untermyer gardens’ timothy tilghman

Q. Hi, Timothy. It’s me again.

A. No, it’s always fun to hear from you.

Q. Needing more plant ideas again. We should probably just as an introduction for people who haven’t come visit yet, which they should this season—just a little quick 411 on Untermyer.

A. It’s this amazing space left by Samuel Untermyer, who made his money lawyering. Precocious, he was a member of the bar before he was 20. Went through corporate merger litigation and lawyering, and was rumored to be the first lawyer ever to win a million-dollar fee from a single client. This was in the late 1800s, and he came to Yonkers and teamed up with William Welles Bosworth, who also did Kykuit for the Rockefellers, and set about designing what he required from his designer, Bosworth, “the world’s greatest garden, the world’s grandest garden.”

Q. Oh. No big deal. [Laughter.]

A. No big deal. So that’s what he asked his designers. So hopefully I never get charted with that sort of request. But Untermyer gardened here aggressively until 1940, and left it to the city of Yonkers upon his death, and the place has kind of gone through this varied history. When I started in 2011, our tagline was, “Untermyer: America’s greatest forgotten garden.” I lived in Yonkers when you and I worked at “Martha Stewart Living;” my job was to go out and find great locations. I’d never heard of this place.

And so Steve Burns, our president, was looking to restore this garden. So that’s what we’ve been doing since 2011. Untermyer had 60 full-time gardeners and 60 greenhouses in its prime. We’ve just worked our way up to four full-time staff with four seasonals, hopefully, this year. So we’re getting close. [The view across the Hudson to the Palisades.]

Q. [Laughter.] Give or take 50-something.

A. Something like that.

Q. Yes, but it’s great, and it’s got some beautiful architecture almost like … not ruins, but remnants. Not perfect, but very beautiful, and it brings it that sense of the old and sort of other-worldly in a way.

A. It’s completely unique. The main garden is a walled Indo-Persian garden, approaching maybe 3 acres. So it’s certainly the largest Indo-Persian garden in the Americas. It’s not one of the only ones, so it’s unique on that level. The view from that garden is at across the Hudson River to the New Jersey Palisades. There’s this grand staircase we call the Allee, which we recently replanted with Cryptomeria, that leads down to a pair of ancient Roman columns that frame the view of the river. Just a really special place.

There’s a 30-foot manmade naturalistic folly of a waterfall that we restored a few years ago when I started to garden that, and recently we just finished construction on the old Rock Garden, which will be sort of a rock and stream garden. So we have water flowing again that partners up with the Temple of Love, and so a huge planting to do there this year.

And another big planting down at the old Gatehouse, which is just a ruin. We’ve stabilized the old ruin of the Gatehouse. It’s just down on the old Croton Aqueduct, which is a state park these days. So it conserves our lower entrance, so we want to spiff that up with some cultivation and bring people up the aqueduct into the garden that way.

So it’s going to be a busy year, but what Untermyer left here the bones of this garden are like nothing else. It’s a true honor to be here, quite honestly.

Q. And they’re lucky to have you I will say, Timothy. But dot, dot, dot, so you need a lot of plants and that’s what we’re here to talk about. [Laughter.]

A. Yes.

Q. Yes. So I was, you know, I remember a couple of years ago when we talked about what you were planting, sort of your annual bedding schemes, your annual color and so forth, and I said, “What do you do? How do you even look—there’s so many possibilities between the seed catalogs and the plant catalogs.”

And you said, “Well first you come up with a theme, Margaret, and my theme is football jerseys.” And I was like, “What is he talking about?” [Laughter.] But I think you were talking about two colors, sort of pick two main colors and go from there, but how do you think about picking a theme now? You know, here we are in 2019.

A. Sure. I mean that’s a great basic idea. And I think color themes, especially for annuals, which should be bold and big and fun, can come from anywhere. So football jerseys, your favorite neon beer sign, a diner sign, anything like that. But here we are in a public garden so we try to get bigger inspiration when we can. For instance, I think you may remember in 2014 we did nothing but marigolds [below].

Q. Yes.

A. Being an Indo-Persian garden, we borrowed from some of the Indian culture, where marigolds are such a celebrated flower. And here in the States, we think a lot of the times, a lot of people think of marigolds as just a typical gas station plant. So we went around and got as many different colors and shapes and sizes as we could and just did a monoculture of marigolds along the canals inside this Indo-Persian wall garden, which is a great palette for annuals, by the way.

The garden is still surrounded by these big mixed borders and we have these great canals that we can offset with this annual color and change that every year. We do a spring planting of tulips, which is big color in the spring. Then we pull the tulips out and go with these annuals, so the marigolds were really great. Just this bright orange and red and yellow and white lines, ribbons along the canals. I think it turned some peoples’ perspective of what a marigold can be around, so that was a lot of fun.

Last year, we had already decided we wanted to do cream and yellow, cream and gold tulips for our planting. So we started with our inspiration for last year’s annual plantings with those two colors, and then I really wanted to grow this particular Gomphrena called ‘Cosmic Flare.’ I think you know it. [Below.]

Q. Yes. Gomphrena ‘Cosmic Flare,’ and when I came to visit you in the peak of late summer or something like that, I was like, “What is that thing?” I mean it was screaming from across the way, right? [Above, gold foliage and pinky-lavender flowers of ‘Cosmic Flare.’]

A. It’s amazing. So it’s a fun, lively foliage plant, but the foliage is a chartreuse-y yellow and then the flowers are these little pompoms, these little balls, cotton-ball size. This particular one, ‘Cosmic Flare,’ is a pink flower and has a tiny orange throat on it, so this yellow, pink, and orange … And gomphrena also comes in orange. And again, here we are in this Indian-themed garden. So we already have the yellow and the white. I really wanted to grow this pink and yellow gomphrena. Orange gomphrena’s a good complement with it, so we ended up with just a pink, yellow, white, and orange theme, which is again, a traditional Indian color combination, and so it started to make sense for what Untermyer left us, and to have fun with gomphrena.

And I got to tell you: this gomphrena, especially the ‘Cosmic Flare,’ I had grown it the year before in my own garden, which has some dappled shade in it and I have not amended the beds, so it’s very average soil. And it was still a very generous plant, and I had a lot of fun with it and I knew I had to use it the following year here at Untermyer. Well, in the full sun and in fertile soil, the thing just exploded. It took off. It was almost more than I wanted to see, but I couldn’t even bring myself to thin it out at all because it was just that big of a show.

Q. [Laughter.] Well it’s interesting you shared with me, you were kind enough before we spoke today to share with me kind of some of your lists and what you were ordering and what you were planning. And what’s great for me to see is that … I happen to have a deficit of ability with Excel spreadsheets, but you don’t. [Laughter.]

And so what you have done is put last year’s and the year before’s—you have them in an Excel spreadsheet. And you have in the first column the name of the plant and the second column the description. And then in the third column, once the season happens, you have notes. And so you really say how the thing performed and what conditions it did or didn’t do in, or if you had to care for it in a particular way, or if it was a flop.

And I think that’s a really great tip for people. I mean you have a lot going on there. You need it for sure and you have multiple gardeners working with you, so you can all refer back to it, yes?

A. No, it’s a huge help. And this whole process, Margaret, is quite bewildering…

Q. [Laughter.]

A. …and I don’t think I’m very good at it, so I need to give myself all the help I can get. And we do use limited sources for our annuals as well. And so to go through and make sure I don’t do repeats of things that I already knew I didn’t want, or to make sure there were some real solid performers do make it back into the list, depending on what the theme is.

Q. Yes. Because sometimes a pretty face, you know, there’ll be something that looks gorgeous in the listings and we buy it and it just isn’t a real performer. And we have to figure out why. So those notes are invaluable.

A. No, and definitely the catalog versus reality is huge.

Q. [Laughter.]

A. And then again, depending on who writes the catalog—I mean we know some growers that have these fabulous plant descriptions that can rival any reference book out there, and you can really get a good idea for the plant.

But for instance, I ordered a Salvia. We did reds a few years ago [above]. That was a color theme simply because I don’t like using red, so I challenged myself that we were going to do all our annuals with a red theme and we got a salvia, it was a cultivar, new cultivar called ‘Mojave Red,’ advertised for the super bloom and it would go on, and have this best color you’ve ever seen, and the biggest flowers you’ve ever seen.

And have you ever seen a bad salvia, Margaret?

Q. A bad salvia?

A. Yes. Aren’t they all pretty great?

Q. Yes. I mean and they’re very different. I mean so I guess bad would be if it didn’t suit your particular taste, but yes. No.

A. Yes. The super-blooming new cultivar came up and bloomed for 5 minutes, and then starting turning color and it was a nice pathetic little plant. And it was just ridiculous, and it was kind of going to be the backbone of one of the major plantings here. So, to take notes like that and to have flops like that, you certainly learn. So we won’t be getting any of those brand new salvia cultivars from that particular series.

And then just looking at the notes to make sure I don’t make other mistakes, because I do try to force some things around here. There’s a lot of plants that we all are used to seeing in pots—that we know are great performers in pots, but we try them in the ground. Some year that does really great and they’re really good surprises and to use them differently is interesting. And other years, they just sit there until you realize they should’ve been in pots.

And so many things, too: The catalog description talks about what exposure and what conditions they need. And they can be really different once you get it into your particular garden.

I know the other thing, brief descriptions from catalogs. We were putting together last year’s yellow and white part of the pink and orange color theme, and I saw this Nemesia. And I’ve never grown Nemesia before. I wasn’t really exposed to it, but I saw this picture and its quick description and I think I ordered 300 plants. And as we were growing that, Andrew Schuyler, one of our gardeners said, “Why so many cool-season nemesias?” I’m like, “Well, what are you talking about ‘cool-season’?”

Q. [Laughter.]

A. And so before we could get them out of the greenhouse, they were already all in bloom and we stuck some into pots, but there was a wasted amount of time growing those plants. It was a wasted crop.

Q. Oh, my.

A. Because of my own ignorance. So yes. The catalog versus reality is a big deal.

Q. And keeping notes. So, you know, Timothy, another thing you were talking about football jerseys, or you hate red, so you made yourself, you challenged yourself to use red annuals. And you know, different themes or the Persian inspirations of the sort of sun colors. Sometimes I think, I march around the garden center and I probably said this before on the show so everybody can just say, “Oh that Margaret, she repeats herself all the time.”

But I go to the garden center and I see one colorful leafed plant like an Acalypha or a Coleus, and I love it; it looks beautiful, and then I march around looking for things to match it and my theme comes from … Do you know what I mean? A plant, another plant. Does that make sense?

A. Absolutely. No, no; completely. One of our canal plantings, I think it was 2016, was because Landcraft nursery out on Long Island, they come out with a new morning glory. It was kind of dwarf. It didn’t turn out to be that dwarf, but it would bloom all day long, and I just wanted to put that on tripods and go around that. So that became the plant, and then I had to find things to go with that.

Q. Right. Right. Right.

A. But there’s nothing like seeing the plants in three dimensions in your hands. I have my list for next year all ready to go, and we’ll grow those in the greenhouse over the next few months, but I have no idea how they’re going to be lined out in the bed until I see the plants. And I may start to see the plants and have to call Landcraft and say, “Oh my gosh. I’m going to need this plant to make this combination work” at the last minute.

Because to see them in a catalog, it’s really hard. You haven’t seen them grown and plants change when they’re next to each other, just like color does. So you see different characteristics all the time and I have never put a design on paper that made it, as written, into the garden bed.

Q. [Laughter.] So you know a lot of people ascribe to this sort of, in a pot for instance, and you have a lot of big pots at Untermyer, the sort of “filler spiller thriller.” I forget what it’s called–spike something something. You know? Something that spills over the edge, something that’s at the middle level and something that’s the upright idea. When you go to do pots, do you look for certain … do you have sort of some architectural items, the upper-level items that you’re crazy about that you use?

A. Oh sure. I mean and definitely looking at pots with that basic design principle is a great approach to it. And then once you know the rules, you can start breaking the rules and have fun with it that way.

But for instance, just last year in our biggest pots, we put a big Tibouchina grandifolia, the glory flower, which has this bigger-than-your-hand leaf, very fuzzy, silvery beautiful plant and it grows into this shrub. It grew to be 5 or 6 feet. It is a problem when you go the late fall winds and it starts to blow itself apart.

And with that, I put another one that you could consider a thriller, it was an Abutilon called ‘Pink Charm,’ kind of this dusky salmon-y pink super prolific abutilon with just a small green, maple-shaped leaf. It is one of the flowering maples. And those two together, the fine texture of the abutilon with the really bold texture of the tibouchina, and then under-planted that with any variety of things, including some spillers.

So I don’t always just limit myself to one of so called thrillers. Sometimes I skip the filler and just have a really big plant. It’s its own specimen. Sometimes I don’t even put a ground cover on that, just to let that plant really show what it’s doing. So I think there’s any number of approaches.

And especially here in the public garden, I have to think about it being on display every day. In the home garden or a private garden, all you have to do is please yourself. So you can really have that freedom to do that I think.

Oh–one other plant; you’ve got to hear about this one, and I just saw it the back of a nursery. Nobody had touched it, and I’ve never heard about it. I’d never read about it. I’d never seen it. Brillantaisia.

Q. Say it again.

A. It’s called Brillantaisia. So brilliant A-S-A-I-A. It’s called a giant salvia. It’s not a Salvia at all. It’s in the Acanthaceae family. But it grew to be 6 to 8 feet, huge glossy leaves, these big panicles of big orchid-like, salvia-like purple flowers. And it was certainly a thriller in some of our pots going down the vista toward the river.

Q. So we talked about the gomphrena and that was a real solid, as I would say, “do-er,” or performer last year. I think you also had used some lantanas and some Thunbergia [the black-eyed Susan vine]. I wanted to talk about a couple of those.  I don’t know if they’re on the list again this year or not, but the thunbergias, especially, which is kind of an annual vine I think of it as, yes?

A. A completely vigorous and prolific in flower annual vine. It’ll grow up almost anything. It’d be really dense and it’ll bloom from the moment you plant it all the way to first frost. And it’s just a really great vine. I have used it on tripods in our Canal borders in the past, a bunch of years ago. And I’ve grown it up wrought iron fence, where it barely had anything to climb onto. Just a big square wrought iron, and it made it all the way up there. Made this big wall of color and in an ugly parking lot, which was a lot of fun.

Then the most fun I’ve had with it, though, is in the Amphitheater at the north end of our garden. Untermyer built an amphitheater for his wife, Minnie, who was a big patron of the arts. And he had this big Chrysanthemum show. So he had these pots that are as big as a car, big rounded pots of chrysanthemums. And he had cascading chrysanthemums coming down off the wall, and then there’s a wall that leads down into our big reflecting pool that terminates the canal. And he would grow these cascading chrysanthemums over this wall.

Well, I wanted to try this with the Thunbergia, and it worked great [photo above]. So I got the buffs and the oranges and the reds and the whites, and we just planted them all along the top of this wall. And it spilled down the 4 to 5 feet, right into the water. It was just a big curtain, but going in a different direction.

Q. O.K.

A. [Laughter.] And I want to use it as a ground cover sometime. I just … I’m worried it’s going to devour everything it’s close to, though.

Q. I see that you have Scaevola, which I think the common name is fan flower, because the little flowers are like the shape of a fan. And people may recognize this one, but you have it in some unusual colors. Colors I don’t … I think of it as sort a lavender-y kind of color, but you have it in some different colors on your list, yes?

A. Right. No, I usually see it in what people call blues or the purples, in a range of those, and a few whites here and there. I’ve always known it as a ubiquitous hanging basket plant.

Q. Exactly.

A. So it’s in the hanging baskets at every retail nursery. And it looks really good. I’ve always been kind of charmed by it, and I’ve never really grown it. And Andrew, one of the gardeners here, and just Jessica and Stuart, they’ll all make fun of me, because I think it’s been at least four years in a row I’ve grown a crop of it,, thinking I want to use it in a basket and I just haven’t ever gotten around to it.

Q. [Laughter.]

A. I’m a bit scared of that ubiquitous feeling and we found other plants that look really good.

And so we’ve given them away to volunteers and such, but this year we found the ‘Classic Pink,’ which is a new color to me as well, and another cultivar called ‘Suntastic,’ which is a bit of cream and yellow with it, so that’s fitting in with our color schemes this year, which we’ve based on some Persian dancers’ dresses who performed here for our big fundraiser last year.

Q. Some Persian dancers’ dresses [above, the inspirational moment]. So that’s where … it’s not football jerseys, it’s Persian dancers’ dresses. O.K.

A. I’m learning Margaret. The redneck Missouri is leaving me year by year I suppose, but-

Q. [Laughter.] That’s Timothy commenting on his own heritage.

A. Yes, yes, yes.

Q.  Any other things that … I saw you have even a Sedge in the mix. What in the world, ‘Amazon Mist’ sedge, a Carex.

A. No and it’s one I haven’t grown. Kind of like salvias—I haven’t found a sedge that I don’t find interesting, that I can’t find a place for. This is a nice little one; it’s not going to get bigger than 1 foot. It has kind of minty-green foliage, very airy. So I thought it would be a great filler texture for annual planting. And if I end up not liking it, we have plenty of perennial beds where I can reuse it in that space. But I’m kind of thinking what would be fun to do is using this one perennial as it’s needing to be growing on, we’ll use our annual beds as the nursery, and when we go to compost all our annuals after first frost, we’ll just pop those out, and they’ll be a landscape size I think.

So I think it could just be a really fun texture that I haven’t seen in annual plantings that often.

Q. So the lightning round as we finish up in the last minute or two. Couple of favorite Cosmos? Any cosmos that you want to shout out for us to have a look at?

A. Well the one I used last year, and I couldn’t get enough of it, and it was supposed to be our main plant and it was going to be one of our thriller plants … and it kind of got eaten up by everything in the bed, but Cosmos ‘Sonata White.’ It’s a dwarf, so it doesn’t need staking. It has really big flowers. It’s really generous with its flower and it made it through the summer heat really well, when a lot of other Cosmos can start to just peter out a little bit. So I was really happy with that one.

Q. O.K. That’s a good one. And because you have this marigold heritage, any that we should look at? I think you used ‘Lemon Gem,’ you’ve gone to Lemon Gem’ time and again, yes?

A. All right. So I completely resist trying to have a signature plant or a signature style. If you can predict what I’m doing, then I can predict it and that becomes really boring, so … But since we have such success and such fun with the marigolds, we always try to put some in. Yes, ‘Lemon Gem’ is coming in, it’s a tiny yellow flower. Last year we used one of the signet marigolds that has a really lacy fine foliage and tiny single yellow flowers. There’s a little bit of scent to it, but just sort of the filler plant. So it’s always fun to use some of the plants that the people see us use on a big scale and work them back into the borders for sure.

Q. Well, good advice. Thank you, Timothy Tilghman, and I’ll give information on visiting Untermeyer Gardens Conservancy in Yonkers, New York, and I’ll hope I’ll talk to you again soon.

A. I look forward to it, Margaret.

more from timothy tilghman and untermyer gardens

• Container garden design, with Timothy TIlghman
• A year of marigolds, at Untermyer Gardens
• Visiting Untermyer and arranging tours (including docent-led ones on Sundays in late April through late October)

(Most of the Untermyer landscape photos above by Jessica Norman of Untermyer; used with permission.)

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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 Feb. 25, 2019 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes/Apple Podcasts or Spotify
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