planting and watering wisdom, from jenks farmer's new book

IN RECENT growing seasons, the “new normal” of a changing climate has sometimes been making me feel like my Northeastern garden has relocated farther to the South. So maybe that’s part of what caught my attention when I saw news of a new book called “Secrets of Southern Gardening: Pro Tips for Success” that was just published by today’s guest, horticulturist, nurseryman and garden designer Jenks Farmer.

He joined me to share some of those tips on smarter planting, especially of trees, and watering how-to’s and more, many of them applicable for wherever you garden.

Augustus Jenkins Farmer, aka Jenks Farmer, is a longtime horticulturist and garden designer and the former director of Riverbanks Botanical Garden in South Carolina, and creates a Substack newsletter called “Plant People.” He is also the author of several garden books, including most recently “Secrets of Southern Gardening.”

True to his surname, he is a farmer, too, specializing in growing and selling Crinum lilies and a few other goodies from his organically managed, 18th-century South Carolina farm.

Plus: Enter to win a copy of his new book by commenting in the box near the bottom of this page.

Read along as you listen to the Sept. 15, 2025 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 (and browse my archive of podcasts here).

garden tips from jenks farmer

Margaret Roach: Hi, Jenks, how are you?

Jenks Farmer: Hey, Margaret. I’m great. It’s hot down here.

Margaret: Well, yeah, I’m in my Southern garden, too, as I say [laughter]. It’s not hot here at the moment, but there are many times this summer that I thought, “Oh my goodness, what the heck’s going on?” And it’s funny because chapter one of your book I think is called, “Our Crazy Southern Climate,” and I thought, yeah, our crazy climate everywhere, huh?—but yes. So your crazy Southern climate, how is it nuts? What’s crazy about it?

Jenks: Even in normal times before things got really crazy, I’ll say we have six seasons. We have a really long fall, so for us, I think it’s very confusing when people move down here from the North and they expect fall to happen in September and October, where really we don’t even get a frost until about Thanksgiving. So that gives us basically two growing seasons in the summer. We can start in April planting things that people plant, squash and zinnias and all the easy annuals, but those kinds of things peter out. So for August, September and October, we have a whole new summer. So we have Crinum lilies are coming into flower in the vegetable garden, okra, and we harvested like nine pounds of eggplant yesterday.

Margaret: Oh my [laughter].

Jenks: So we have that sort of two separate summer seasons. And then for us, winter can be just outrageously variable. So we can go from 70 degrees on New Year’s Day to 13 degrees that night, and it’s always been that way in our climate, and that’s very hard on plants. But I think the key for people who are moving here, or even people who are thinking about visiting, is remembering how variable it is and that we can have absolutely spectacular beautiful days in February and again in September, but then like tomorrow it is going to be 95.

Margaret: And where are you, what city? Where are you exactly located? What’s the name of it?

Jenks: It’s near Augusta, Ga., so people will know exactly where that is, but it’s a little town called Beech Island. There is no beach and there is no island here, but we’re right in South Carolina along the Savannah River, not too far up from Savannah.

Margaret: O.K. So speaking of funny names, I like that you have a Beech Island with no beach and no island. Reading as a Northern gardener in the new book, I love noticing some of the regional differences, not just in plant choices or the timing of when you do what and so forth and how you do things, but also the common names that we use in different regions and other vocabulary choices. Like a wonderful more Southern native—not where I am, but more southerly—Chionanthus virginicus, that I can grow too, though. I call it the fringe tree and you call it-

Jenks: Granddaddy graybeard.

Margaret: Granddaddy graybeard [laughter]. I love it; I love it. It’s like I never heard that. It was like I was so delighted by these kinds of things. And it’s just one of the many Southeastern natives that’s hardy up North, too, and has been marketed as a garden plant like Oxydendrum, and bottlebrush buckeye, Aesculus parviflora. I mean a couple of species of Fothergilla, we think of them as Southeastern natives, but they’re hardy up here and they’re popular garden plants in a lot of the country, and maybe they were native up here, too, before the last glaciers. Who knows, right?

Jenks: Oh yeah. It’s such a crazy question with nativity because things move and they have, and then a lot of times what we think of as native was only based on what European travelers wrote about when they got here and what they saw. So maybe they didn’t see the Chionanthus that was growing on the shore of New Jersey-

Margaret: Or now they’d use the fossil records, of course, as well, so there are some more records compared to back then, but yeah. But it’s really interesting that we have a lot of overlap in plants even though we’re far apart and our climates are supposedly so different.

So it’s fall planting time in a lot of places, and there’s this section in the book about planting, especially trees and other woody things, I think. And a lot of your advice—and after all, I mean the book is called “Secrets of Southern Gardening: Pro Tips for Success”—and there were so many tips, so many things that reminded me of when I’ve violated them, how it went wrong [laughter], and the things that we really need to remember.

And I just loved your way of explaining the why and the how of when you buy a tree in a nursery pot or ball-and-burlapped and so forth, and figuring out what level, how deep it should go, and how to get it ready to be in the hole in the ground that you’re going to make for it and how to do aftercare it, how to water it.

I just thought, for instance, that was one of the really great lessons, and it might seem basic to people, but I think a lot of people just take it out of the pot and put it in a hole the same level it was at in the nursery pot, and that’s not always a good idea, is it?

Jenks: No. So I’m a nurseryman and I grow mostly in the ground, but I have some things in containers. The goal in the nursery is to have a potting media that makes that plant look great in the nursery. Because growing in a pot with constant irrigation, with wind, is a whole different thing from growing in the ground. So my potting media, and not just me, but any nursery’s potting media, is about our success so that we can sell that plant. It’s not about success in transplanting, right? And a lot of big nurseries especially are looking for ways to save money, so they’re incorporating waste materials into their potting mix. A lot of bark gets mixed in now down here; peanut shells gets mixed in.

Those things are fine for the nursery, but they’re super-dry, so anytime that I’m planting—I do landscape planting, design work—if I can, I saturate those plants, even the big ones. I’ll take on a job five or six baby pools [above], and fill those pools up and try to let those plants soak overnight because it can be so difficult to get that potting mix wet.

Then the next thing I do is when I take that out, I beat off a lot of that potting mix and take it away. I want, especially for woody plants, I almost bare-root them and put them back in the ground. Now I’ll mix in some of that bark; I’m not saying it’s terrible stuff, but for root contact with your soil, the best thing to do is to get rid of a bunch of that.

Margaret: And the other thing is the depth. There was one picture in the book showing I think a tree that had just gotten planted or had just come out of its nursery pot, and I mean, it was so at the wrong level. And yes, you point out in the book, you couldn’t see the root flare where the trunk meets the uppermost roots, and they sort of do flare gradually outward to begin the root zone, and it was like bark was buried, and that’s often the case. It’s not ideal.

Jenks: That particular tree, that was one I bought for myself, not for a client, and I splurged on this little 2-gallon tree from a very good connoisseur’s nursery [above left]. But when I got home, I realized that it was 2 inches too deep, so 2 inches of that soil on the top of that pot, I had to cut it off with a hand saw. And this is not uncommon.

Again, I’m saying this is from a good nursery. A lot of our plants come from box stores and nurseries that are really big, and they’re even worse. So that top layer can inhibit the plant growth first because the bark that’s inside that layer [above right] is subject to rot and therefore subject to lots of pests.

Margaret: And it can stay all moist and rot, almost, like funky.

Jenks: Fungus. And then on a larger scale, because we do some big tree planting with tree spades where we’re planting like 10-inch trees, those trees often have the same thing, the same problem, but that soil on a bigger tree will actually inhibit the growth of that trunk below ground. So you end up with this sort of narrow trunk that’s below ground, this little spot that’s restricted, and then you slowly get a bigger trunk growing bigger girth above ground, but you always have that weak spot. So for us, in hurricanes, that’s terrible, because that tree’s got a built-in place to snap.

Margaret: And even without a hurricane [laughter], improper death, especially too deep, can be a killer. It sort of almost suffocates the plant, can’t it potentially?

Jenks: Oh, yeah, definitely. And I just see this over and over, and one way I wrote this book was from the perspective that a homeowner who may not be planting their 30-gallon plants—they might bring in a landscaper to do it—but they need to know this, so when they’re out there watching their landscaper work, they’re making sure it’s done right. Ultimately, it’s your responsibility if you’re hiring somebody to do it. It’s like with me hiring a doctor, I also pay attention and read up about the issues so that I have some idea that what that doctor is saying is making sense. Does that follow?

Margaret: Yeah. And the other thing that you point out in the book, which I never see anybody except longtime horticulturists with old-style training do like us [laughter], but it is so essential: I see people make that hole, get the plant in the hole, pack it with the soil, get it all tamped down, and then try to water it. And it’s like, what?

Jenks: And that’s the best case that they try to water it. A lot of times you’ll see a company say, “Oh, we’re going to turn on the irrigation.”

Margaret: Well, that’s hopeless to irrigate big, extensive new plantings and stuff like that. It’s not going to do the job for all those transplants.

Jenks: So we were planting this morning some 30-gallon magnolias, and I took a little video of us mudding it in. I don’t know if you can embed a video.

Margaret: Yeah, I can. And you say, it was so funny because in the book you explain this technique, mudding it in [or muddling it in], which I call puddling it in. And I don’t know who told me to call it that a million years ago or whatever, but it was the same technique, and I thought, I’m the only person I know—when I’m with people where I live and stuff’s being planted—I’m the only person I know who does this.

Jenks: Man, I’ll tell you, this is something I struggle with my guys all the time. When we’re planting on a job, I want that hose running all day long, because every plant… And we’re just moving it. We do that mudding in where we’re jamming the hose down in the ground-

Margaret: Before we’ve, again, totally fully backfilled and tamped and made everything look perfect.

Jenks: Exactly.

Margaret: So tell us, just I should backtrack and said, what is mudding in or puddling?

Jenks: O.K., so you dig your hole, you put your plant in there that you’ve knocked a lot of soil off of, and you have your water running the whole time that you’re backfilling. The reason for that is that no matter what you do, there are always going to be air pockets that you can’t see and can’t tamp in, but that water running creates like little mudslides and it fills in all those spots.

Margaret: So you muddle, I puddle. [Laughter.]

Jenks: And see, I love doing that and I’ve loved doing that since I was a kid. Every time I do it, I remember when I was a kid punching that hose down in the ground and making little tunnels.

Margaret: Because these plants only have one chance to get a good start in our soil, don’t they? This is not a time to skimp or to stress them out further. It’s enough already.

Jenks: Absolutely. Absolutely.

Margaret: Transplanting is enough stress, even if it’s done correctly; it’s a stressor. So we want to give them the best possible.

Jenks: Absolutely. My design clients will ask me sometimes, do you guarantee your plants? I’m like, no, these plants are like puppies. I’m going to plant them right, and if they’re planted right, they’re going to thrive. And I have no doubt of that. Its aftercare is important, but that first 20 minutes is critical.

Margaret: Sort of also related to giving things a good start is—and again that you cover in the book—is deciding where they can be placed in the microclimates or the different areas of one’s landscape, one’s garden, one’s home garden. And you make the important point that I think a lot of us don’t think about. We all as gardeners, I think, think about is it a sun plant or a shade plant? But we don’t think about soil moisture as much, right? And so we’re grouping for light a lot of times. But that’s not the whole story, is it?

Jenks: No. And especially with us, we can go from red heavy clay to literally 100 feet away can be like white sand, and those are totally different plants. They require totally different soils and drainages, and different plants thrive in those different soils.

You mentioned microclimates, you’re probably going to think this is funny, but I was looking at a place the other day and it was like a north-facing wall, and it’s a little heavy clay. It’s shady all the time; it doesn’t get any winter sun. And I thought maybe I can plant some anemones there because for me, that’s a cold microclimate that I might be able to make some anemones, some more Northern plants, thrive.

Margaret: They wouldn’t just bake and sulk because of the heat.

Jenks: Yeah. But I think generally when people think of microclimates, they think of how can I fit this somewhere warmer?

Margaret: Right, a warmer place. Right. Well, that’s a good point also because I remember a million years ago when I wanted to have this magnolia. When I was first making the garden, I wanted to have a magnolia, an early-blooming magnolia, but a different one. And I asked the best local nurseryman and he said, well, here’s one, and he pointed one out to me and he said the flowers of this one will never get ruined by a late frost if you plant it like the kind of spot you’re just talking about. More in the east or the northern side of your house, somewhere where it’s not going to be toasted all the time [laughter], where it’s going to wake up later, not wake up early. And he was right.

I’ve had the thing 30 years or something. ‘Ballerina’ it’s called, one of those Loebner hybrids; I don’t know how you pronounce the man’s name who developed the the series of them. And he was absolutely right. He was looking for the microclimate that would delay its awakening, those buds, prevent from becoming vulnerable.

Jenks: And I just see there’s an example of when you’re a much better gardener than I am because-

Margaret: Oh stop [laughter].

Jenks: I’ve just accepted that those magnolias always have a brown period, and I’ve taught myself that we might as well call it pretty [laughter].

Margaret: They are beautiful creatures though, aren’t they? So I was really drawn that whole chapter that involves watering in the book, called “Mindful and Efficient Watering.” I loved it. It sounded very Buddhist [laughter] because frankly, growing up as a Northeastern gardener, we used to have that old sort of proverbial inch of rain a week kind of thing. It used to be more regular, and it’s not the case anymore. So I am not as expert at watering. And you had this one tip about a 5-gallon bucket with a hole in it. Tell us about that [laughter].

Jenks: Yeah, so that’s a real redneck way to do it, but-

Margaret: But I loved it. I loved it. It’s great.

Jenks: It works. We do that a lot. You can buy these tree bags that are basically a big water balloon with a slow drip on them, but those things are super-expensive. And we just take a 5-gallon bucket and put a nail hole in the bottom, and fill it up once or twice a week and let it slowly drip.

And then the other tip, I guess this is what makes it really pro, is that we put a red spray paint mark on all those buckets, because you sure as hell don’t want to pick up that bucket and fill it up with water to carry it to water something and have its squirting water out on your sock the whole way.

Margaret: Right. So you’re placing this bucket with this little hole in it, you’re placing it near specimens that need that extra help during tough times or whatever. So they’re going to get this extra water. I forget what those vessels are called, those clay vessels. What are those? Anyway, there are traditional vessels like that that are fancy that do this? Olla, is that the word: Olla? Yeah.

Jenks: Remember I remember that word, but I’ve never said it.

Margaret: [Laughter.] No, me neither. So the point being, however we do it, we have to be attentive, mindful, as you say about watering, and especially when plants are getting acclimated.

Jenks: All different plants have different needs, and that’s a technique that we use mainly on new plants. But in a drought summer—and we’ve been really lucky for the past three or four years, we’ve had very wet summers—but September, October is always very dry. There are times that there are certain plants that just need that little bit of water to thrive.

Margaret: So we have something else in common besides muddling and puddling [laughter]. We both have discovered the beauty of the nighttime activity in the garden, the night shift, as I call it. And you actually hosted this year a moth event that I think you called the Moth Ball, ha ha ha. Very funny.

Jenks: We did, we called it the Moth Ball, and I did this graphic for it that my young friend said, “Nobody’s going to come to that because it looks like it’s a techno-dance.” But we had ended up having 70 people. We had three entomologists from three different universities who set up screens while people grabbed a drink and some hor d’oeuvres and wandered around from screen to screen, so they got three different interpretations of the night insects that were attracted to these screens. I guess I should have said each screen had a different kind of light on it, so it attracted different insects. It was primarily about moths, but the night shift, as you call it, was all there.

Margaret: And the closing chapter in the book is about that, which is wonderful because so many of us gardeners, we know our place so well, but not after dark.

Jenks: And I realized in writing this, not that many people really want to garden after dark, but nonetheless, it’s really important that we understand it, because the world and the garden after dark is absolutely as active and really maybe even more important.

Moths are really basically more important pollinators, I think, than butterflies. And then all the decomposers come out. It’s critical that we understand that so that we treat—especially with light—light can be a problem—but also with other things that we’re doing, we have to be aware of herbicide and fertilizer damage, and even excessive raking and cleaning can take away the places that those larvae need, the moth caterpillars need to pupate.

You actually inspired that whole chapter, Margaret. Thank you so much.

Margaret: Well, because I’m moth crazy. So the new book, Jenks Farmer, is “Secrets of Southern Gardening: Pro Tips for Success.” And as I said, even as a Northern gardener, I found so much information that appealed to me. And so it’s wonderful. I always enjoy talking to you, and I hope I’ll talk to you soon again, thank you so much.