From away to garden.com and Robinhood Radio.com, this is Away to Garden with Margaret Roach. You're a weekly invitation to dig in and grow. Not so many years ago relative to the history of horticulture, even a now ubiquitous phrase like pollinator plant wasn't part of our everyday gardening language and mindset the way it is today. Our collective consciousness about the importance of native plants has grown fast and with it have come more new words for our vocabulary. One phrase that I've heard a lot lately is keystone plant. An expression I probably didn't even know five years ago describing native species that are disproportionately important to local ecosystems, the sort of powerhouse plants of all. I wanted to learn more about just what Keystone plants are and which ones belong in my garden and why. And Uli Lorimer, Director of Horticulture at Native Plant Trust, is here to help explain all that. So more in a moment, but first, these messages. Underwriting support for a to garden provided by Colorblends, wholesale flower bulbs, a third generation bulb company offering top-sized flower bulbs directly to landscape professionals and ambitious residential gardeners on the web, Colorblends.com. And by high-moving seeds, Wulkevermont, Professional Quality Vegetable, Flower, and Erbil Seeds that are 100% organic and non-GMO project verified. On the web, highmowingseeds.com and by White Flower Farm offering a wide range of carefully selected and expertly grown garden plants. On the web, whiteflowerfarm.com Today's guest, Raleigh Lorimer, is the director of Horticulture at Native Plant Trust in New England. And he also writes the Ask the Gardener column for the Boston Globe. He has devoted his career to Native plants, and I'm so glad to welcome him back to the program today. How are you over there across Massachusetts from me? Trying to stay warm, but delighted to be here. Good luck with that. So as I said in the introduction, I think the phrase Keystone plants, it's one that's spoken a lot lately. Do you remember the first time you heard it? I probably put myself in your camp maybe about five to seven years ago and would also really credit Doug Talami for bringing this to sort of more of the public's awareness. You know in researching the the concept itself it dates back quite quite a way several decades ago when it was first coined and came out of oceanographic research. And I think it's one of these concepts that I think has generated a lot of discussion, at least in the ecology world, generated lots of sort of associated terms like indicator species and flag ship species and functional groups and all these sorts of things that I think have really helped move the needle and how we think about the role of gardens and the environment and how they interact with each other. So even before it had this name, Keystone plants that, as you said, Doug Talami of the University of Delaware and Homegrown National Park as non-profit, has helped popularize in more recent years. It was kind of out there. I forgot it came from the ocean. I forgot it came from that, right? A doctor pain who coined it and had discovered that when you remove one particular species in this system that he was studying, it had a cascade of negative effects and he thought, like, this is sort of akin to that keystone that sits at the center of an arch and keeps the whole thing together. And if you remove it, then these existence collapse. Right. Right. And so originally, I guess as native plants have become more and more the subject of research and more widely used and so forth. I mean a lot of the research initially was probably comparing the impact on the ecosystems of native versus non-native plants. I would imagine that's probably where it began, yeah. and then more like natives compared to one another. And from there we went dot, dot, dot, we found the keystones, the ones that were the most impactful, yeah? Yeah, I think that's generally the- I mean oversimplifying, excuse me. Well, but I think that all that, you know, what I've come to recognize nowadays is that, that, you know, ecological horticulture is really multi-disciplinary in which you have to draw from data sets and pools of information and expertise from the entomology world, from the ornithology world, from those who study fungi and that the interactions of particular insect group with plants has probably long been well known, but unknown to the horticultural world. And so putting together these pieces and connecting the dots as you just did. Mm-hmm. And some of the, and once that became more of a, you know, these by Doug Talamis team and other colleagues in the native plant world. Some of the statistics, some of the numbers are pretty astonishing. I remember the one because he has focused us a lot on the importance of caterpillars of the lepidoptera and the caterpillars and how they support the food webs so critically. I think it was like 14% of native plant species support 90% of the caterpillars that then in turn support the terrestrial food web. Like these, it's this small number and again those sort of keystones. Yeah. Yeah. I mean, if you, we could define this sort of in the modern sense as something that has a disproportionate impact on biodiversity far beyond its abundance on the landscape. And I think that drawing the connections with butterflies and moths and the earlier stages of their lives and the fact that I read 96% of all songbirds need insects to be reproductively successful. And I was really astonished to hear that. And then a friend of mine, Dr. Desiree Narengo, published a study a few years back kind of quantifying this for Carolina chickadees. And I often cite this research that a pair of chickadees requires more than 5,000 caterpillars to raise a brood of chicks in a season, which is just a like a stupifying amount of caterpillars. You think about it and where are they going to find it? I always say that caterpillars are the baby food of the songbird set. You know what I mean? That's my popular way of saying it. You know, the, because really that is even birds who are not bird species, songbird species who are not as adults, as predominantly insectivorous at that time in their life cycle and their life history when they are raising a brood. that is the baby food, that is the go-to stuff. Even if they you know use seeds much more or other creatures, other things you know other sources of food much more especially seeds. But you know there's a reason that you know seeds and fruit are resources that are more abundant in the later parts of the year. And there's this beautiful convergence of not only plants emerging and flowering, but also all that insect life and biodiversity and biomass that's so well timed with the plants all coming together at the same time to really... you know, I was just thinking that despite the fact that a pair of cat chickadees might clean out 5,000 caterpillars in an immediate vicinity, there's still more for all of those maels and butterflies to complete their life. So, I mean, you know, there must be literally tens of thousands hiding in the forest, if not more, that we never see because because they're all up high in the canopy. Yeah. And apparently the caterpillars are protein-packed, I guess. I mean, there are really dense form of nutrition, so that's critical for those little babies too, I think. Yeah. But I think what one of the big shifts here, I think, is that we may have assumed that adjacent nearby natural spaces were intact enough to support all of these organisms and that we could really focus our gardens on just being pretty. And I think that there's a growing realization that the health of forests and meadows and so forth isn't maybe not as great as we thought. And that, you know, gardeners who really wish to make a positive impact are thinking what kind of intentional choices can I make in my gardens to help to help kind of create wildlife corridors or provide resources that just aren't reliably in the environment anymore? I think a lot of this is what drives this movement forward. So at Native Plant Trust and then dot, dot, dot, sort of if we can translate some of the lessons of how you use, how you think about when you and your team go about the work that you do, deciding what plants to use. You have propagation operations, you love a lot of different things going on besides two properties and more, I guess, that you're also conserving, but the two primary locations. And how do you decide kind of what the role of keystone plants,

like how often does this come up in your work

and how that should we gardeners,

like be thinking about keystone plants? Because I mean, can we even list the keystone plants? It's not the same in every region. No, and I think about know, one of our core missions is also to educate the public about all the stories around native plants. And so we do quite a lot of research in the winter to try to uncover what those relationships are between a particular species and maybe an insect herbivore or a specialist bee or specialist pollinator or if it's a host for a particular butterfly or moth. And I think that we strive to find ways to incorporate those plants into our displays the belief that we're providing not just something beautiful for humans to enjoy in a sense of place, but also a missing resource for these organisms. The challenge, I think, which in any garden is, how do you find the balance between species diversity

and biodiversity and you could make the argument

that lots of different things is a net benefit for the wild

versus a design that is legible to us

that we can make sense of and that there's sort of a balance

and a middle ground between, you know, what we get out of gardens and what we're providing for for the local wildlife. So I think that's always a little bit of a push and pull where we always want we love plants, we want to grow everything we possibly can, but sometimes the site conditions don't allow us to grow everything. So you have to make hard choices sometimes. Right. And finding out which ones though are the keystones of our area, I mean, that's, it feels like that's a really good educational first step. I mean, understanding that knowing what they are both the woody plants and the herbaceous plants. I mean, I know that you know, a drug tell me a lot, he wrote a whole book about oaks and oaks are in various habitats, powerhouses, you know, definite powerhouses and it all makes sense. And then there's other woody plants, but also again, you know, herbaceous perennials and so forth. Yeah, a lot of herbaceous perennials too. I mean, there's some good resources, you know, we, The National Wildlife Foundation has some great lists that are based on his work.

You know, I'll mean, there's some good resources, you know, we, uh, the National Wildlife Foundation has some great lists that are based on his work.

You know, I'll say that there's, that there, there's not like a one-stop shop to figure out everything that there is. And, and a lot of the research now is skewed towards, uh, catapillars, um, which, you know, we've connected really well with bird life, but there's still a whole lot we

don't know about insect herbivores, other stem cavity nesters, organisms that use plants as habitat, not necessarily just as food. If I take a step back, I think that, you know, we're all trending towards this greater awareness because there's a realization that our choices have real positive impacts for the environment. I think that's really what this is boils down to. And that, you know, welcoming native plants is a welcome step, but you don't have to be a purist about it in your gardens. You know, horticulture has introduced a lot of really beautiful plants from other parts of the world. Some of them will say have turned out to be harmful as they have escaped, but the reality is that wildlife interacts with all of them in one way or another. And I think that Doug Tylemi's message of aiming for 70% native is a really good one because it's a goal, it's a journey upon which each individual gardener can decide how fast and how quickly they work towards it. as long as you don't lose that intention of trying to make a forward thinking choice that's going to help protect what remains of our world. So if, for instance, I want to think about, I think what we're, one thing that I'm here you say is that the keystone plants for caterpillars might be a little bit different than the list of keystone plants for, say, bees, like pollinators, yes? Yes. So if I wanted to think about pollinators, for instance, and I wanted to think about perennials, herbaceous perennials, flowering perennials, would I be looking probably, and I'm going to guess in like the astro family, the sort of daisy like flowers and also like maybe the mint family because that's where I see a lot of the action in my garden, you know. I'd throw in the carrot family too, the APA. Oh right, the umbles, the things are really wonderful. Right. But you know what a lot of those, particularly the Astro family, what they share is a general flower shape that accepts all colors. It doesn't matter if you're a big muscular bumblebee or a small or a sweat bee or something. Accessibility. Accessibility. And now there are, and because of this long relationship that flower shape and insect shape have driven specialization, you know, it's good to have the generalists in there and you also need to provide for, you know, specialists that need, it's not just flower shape. Like I was just thinking about spring beauties and the spring beauty mining bee And here's like a really close little relationship that that bee needs The particular nectar and pollen of that plant to be reproductively successful and nothing else There's no substitute for it and so I think this is where favoring a Native species to support those specialists is a really good. There's a strong argument he made for that because the generalist could use that as well as many other things. Absolutely. Right so we need to write. Yeah you could have a law in full of crocuses and spring beauties and you get both the support for the specialist and maybe a little bit more design choices with the crocuses, but we know crocuses aren't going to take over the world and even if they did that wouldn't be so bad. Right, so okay, so what we're saying is we're going to look in the case of perennials, for instance, and really no matter where we are, because morphologically and structurally those those three groups plants that we just name as families are there's structurally there again accessible. We're going to look probably in those those families and and I can give the links to you alluded to like some of the websites that may have list by biore of Keystone Plants and so forth. I can give some links with the transcript of this show over on our way to garden.com where people can do a little homework. But again, you have to know what your Keystone Plants for, what you're looking for, which is a little more complicated. Well, for pollinators, I think there's another really fantastic resource that's by a man named Jared Fowler. Oh, yes. F-O-W-L-E-R. And he has these really wonderful lists of native perennials and all of the B species that they support or that they've known to associate with. And you get, you know, there's plenty of options in composite family and mint and carrot family. And then loads of others. And that gives you, again, that sort of research-based, database background to inform your choices in a garden of which perennials you can include to support not only a generalist, but also with an eye to the specialists. Right. And in Woody plants, I mean, I mentioned, you know, that Doug has taught us so much about the oaks, but in Woody plants, are there some, I mean, you know, for instance in your work at Native Plant Trust, are there some, uh, general of Woody plants that you feel like are real power houses that

you're you know you see their contribution as outsize kind of yeah I think of uh first one comes to mind are viburnums oh and you know viburnums I think are are you know there's there's a good deal of diversity. The flowers support a lot of pollinators. There are a number of leopard optra that host on viburnums, and then you have the added benefit of really nutritious fruit that birds rely on in the fall. And so you really get a whole different sets of interactions as the season goes by. And then I think from the human perspective, they're beautiful shrubs, they've got wonderful fall color. If you want an alternative to your burning bush, like put in a vibranum nudum and you won't be disappointed. So that comes to mind a lot of the vaccinium. I was going to say crazy about blueberries. Crazy about blueberries. Yes. And for all the same reasons, that flower supportive variety of pollinators, the birds love the fruit. You have to to compete with them a little bit to get the fruit, but fall colors, exceptional. There's all these things that converge and I think make them real, keystone species in a garden. With the blueberries, I've never really picked any of, I've had some of them for the Shubs for 30 plus years. But I'd sort of tucked them all in these kind of what I call bio-headages, these kind of, you know, at the borders of the property, all these woody plant combinations, you know, they're everywhere. There's a few here and a few there and a few everywhere. And the insects and the birds love them. They're not for me. And what is for me is that the gorgeous red full of color and you know they're beautiful, they're beautiful plants, but they don't need any much, really much attention yet they draw in all the wildlife. Yeah, and I think this is a good segue to the idea of, you know, the right balance between, you know, what I would call and gardens. So making sure that there aren't leaves on your stump patio that are gonna cause you to slip and fall. And that balance with what I would think of is really ecologically forward practices like leaving stems, leaving the leaves, the idea of creating soft landings, your intentional hedges that are not for you to harvest from, but are for the wildlife. Right. Intentional brush piles. I really, my friend, Edwina Vungal and her snake habitat that she created. Yes. I love that. I absolutely love that. Yes. So I think that's the sort of another perspective to bring into this conversation that you can really maximize the impact of keystone species by pairing those plants with a balanced approach of how you maintain your garden. Because there's not much point in planting a viburnum if you're gonna then blow all the leaves away in the fall and rake it up and then replace it with wood chip mulch. And so, Right, let alone an oak tree where, you know, I mean, where goodness knows how many creatures are gonna be in the leaf litter of that tree that's gonna to be fairly persistent. Absolutely. You know, you don't want to, you want to try to let that be, as you say, like a soft landing a place that can, can perpetuate and be largely untouched, you know. Yeah, and I think, you know, you start to put together, you know, this, this concept of, a real, you know, workhorse is another one of these work horse species that gets thrown out. That idea and the fact that gardens aren't just for us anymore and combined with some really, you know, conscientious and ecologically sensitive maintenance practices, And the result is a garden that bursts with life that provides all of these wonderful opportunities for you to observe to be inspired to you know gain all of the benefits of gardening which which we know is less stress and more happiness.

Yeah. Well, one more, we have like a minute just left. One more, um, tree or shrub, for instance, that you want to shout out because I just think the witty plants are so important and they're permanent, you know, fixtures in the garden. I'm gonna call out dogwoods. Yay. Oh, good. Good. No, because I think you have both, know the beautiful small flowered you know cornice florida and it's red fruit again and the interactions and then all of the wonderful shrubby ones that exist in our wetland margins that that have similar similar to the viburnums the ability to draw different groups of

organisms throughout the season. So you know, my top two are gonna be dogwoods and vibranums. Okay. Well, Uly Lorma, it's always fun to talk to you and Yeah, Keith, don't plant. I think it's been one of the phrases of of the year for sure. I've heard it more and more and more all the time. So I look forward to talking to you again soon.

Thanks for making time today.

Absolutely, thanks for having me.

Stay warm over there, okay?

We'll do, we'll do.

You do the same.

Thank you. And thanks to all of you for tuning in. Now don't miss an episode. You can subscribe, free to the podcast version of the show on Apple Podcasts or Spotify. you can find me anytime at away to garden.com and on Facebook and on Instagram as

at away to garden and happy gardening on Facebook and on Instagram as at away to garden. And happy gardening, including with Keystone Plants, meantime. Underwriting support for Away to Garden, provided by Colorblends wholesale Flower Bulbs, a third-generation bulb company offering top-sized flower bulbs directly to landscape professionals and ambitious residential gardeners on the web, colorblends.com. And by High Mohing Seeds, Wolcott Vermont, Professional Quality Vegetable, Flower, and Urbal Seeds that are 100% organic and non-GMO project verified. On the web, HighMoflowerfarm.com

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