Ep. 267 Growing on rocks: Exploring gravel gardens | #GoodGrowing

Chris Enroth: 00:05

Welcome to the Good Growing podcast. I am Chris Enroth, horticulture educator with the University of Illinois Extension coming at you from Macomb, Illinois, and we have got a great show for you today, Gravel Gardens. I'm seeing these things everywhere, it seems like. Well, not everywhere. I'm seeing them online everywhere, but we're gonna talk about them today.

Chris Enroth: 00:24

And you know I'm not doing this by myself. I'm joined as always every single week by horticulture educator Ken Johnson in Jacksonville. Hey, Ken.

Ken Johnson: 00:32

Hello, Chris. I got lots of questions.

Chris Enroth: 00:36

I will do my best to have answers. But I will also have my own questions. So we might just be asking each other questions. This will be a very Socratic way of So we we need we need more help then. So we better also bring on horticulture educator Emily Swihart in Milan, Illinois.

Chris Enroth: 01:00

Emily, here we go. Let's do it, gravel gardens

Emily Swihart: 01:04

Hi guys and yes, I am very much looking forward to this conversation. I'm a questioner at heart. I've asked a lot of questions and so this might be an interesting podcast and it's an interesting concept so I think that's appropriate for us.

Chris Enroth: 01:23

I agree, I agree. So maybe I don't know how well versed all three of us are on this particular topic, but I did buy the book that I've I've read almost all of it.

Chris Enroth: 01:41

There's a few sections that I skipped. But I've read most of it. And I will I will try to do my best to convey what they talk about in this book. And and as we discuss gravel gardens, Ken, I trust you've you've listened to all of the other podcasts on this topic, correct?

Ken Johnson: 02:02

I got through one and read some stuff. So

Chris Enroth: 02:05

okay. Well, that makes that makes Emily the expert.

Emily Swihart: 02:11

Oh no, Oh, dear. You know, I did. So the the person who, like, we're gonna probably be referencing the most is a fellow midwesterner. His name is Jeff Epping. He was, author or co author of that book, Chris.

Chris Enroth: 02:25

co-author Jeff Epping and Teresa Woodard.

Emily Swihart: 02:28

Yeah and he has really been a huge advocate for this style of gardening especially throughout the Midwest. We had him on a program that we hosted a couple years ago I got to listen to him talk about this concept, you know so he's been doing it for for many many years has a lot of experience with it, is a fantastic gardener and so you know I read a lot of his stuff listened to a lot of the podcasts that he's been doing, kind of gleaning most of my knowledge from him. It's interesting I still like I said I do have a lot of questions but it is one way of gardening I guess is what I would say. It is one style, it is not a one size fits all like none of the gardens that we talk about rain gardens, know xeriscaping, gravel gardens, know like none of those things are one size fits all so there's perhaps a time and a place for this also.

Ken Johnson: 03:27

Yeah. Sounds like you're the expert. Yeah.

Chris Enroth: 03:31

There it is. I see a degree on your wall behind you. Just kidding. It's a background.

Emily Swihart: 03:37

A virtual let

Chris Enroth: 03:40

me clean that off real quick.

Emily Swihart: 03:42

Yeah. So let's let's okay. Let's mean, let's dive into it. So like none of us are experts. This is relatively new way of gardening.

Emily Swihart: 03:51

I think we maybe can use some of our own experiences and expertise also to kind of decipher what this might mean for our gardens, for you know community gardens, Illinois gardens, but what are we talking about? We've said gravel gardens like who wants there's a certain way of building them there's like a prescription. Chris do you want to kind of outline that for us since you have the book?

Chris Enroth: 04:18

Sure, So a gravel garden is it is a garden made of gravel. But there is a specific build order as Emily mentioned. So and it is this I think part that gives lots of people who learn about it the most trepidation about it because it's a big lift. So a gravel garden is essentially, you excavate about five to six inches of soil, and then you replace that with gravel. Now in this book, do various case studies of the types of gravel and the depths.

Chris Enroth: 05:03

Some of them mix in gravel with the soil, like they'll they'll mix in the bottom two inches with soil and gravel, and then they'll add four more inches of just straight gravel. It varies. It doesn't necessarily seem like it looks like people are using what materials they have in their region, in their area. This particular book goes into projects from from like Southern US, Midwest, East Coast, the West. We go over to Europe, Germany, England.

Chris Enroth: 05:39

So it's all over the globe, so to speak. And I will say that it's that initial lift of excavating about five inches to six inches of soil and replacing that with gravel. Now, as the more I read, I there is, it's kind of hidden a little bit in one of these chapters here, where where Jeff Epine, I think, makes the comment that you don't have to excavate the entire planting bed. The most important thing is you're excavating around the edge. You're creating a significant lip, five to six inch lip between your existing soil and the new gravel garden.

Chris Enroth: 06:24

And you can even pile on to create like a mounded effect of your your gravel garden landscaping bed. But it is important for this style that you have about five to six inches of gravel on top of that soil. So did that make sense the way I explain things? I see it in my brain. It doesn't necessarily translate to words.

Ken Johnson: 06:49

So you wouldn't have to necessarily excavate. You could just put six inches of

Chris Enroth: 06:54

rock Yes.

Ken Johnson: 06:54

On top of the soil

Chris Enroth: 06:56

Yep.

Ken Johnson: 06:56

In theory.

Chris Enroth: 06:57

And And then and then put a bare air

Ken Johnson: 06:58

up to to contain it, maybe.

Chris Enroth: 07:02

A lot of folks would use like pavers or edging concretes concrete or stone. Yes. Some kind of a barrier to keep the gravel from spilling out into the walkway or lawn or wherever the gravel garden was.

Emily Swihart: 07:20

Yeah I think that's one way of doing it in my mind and to answer your question I think you did a nice job of describing it from at least my understanding like that's how I would have kind of described it too like you can excavate and I think the point for excavating was if there's a high weed pressure or a large weed bank a weed seed bank in that soil they mentioned that quite a bit as a way of controlling weed germination is removing that soil, and then putting the rock on top so you could excavate down or yeah you could just pile it on top of a soil. I also kind of thought about, like when we when you were describing it and when I was reading about it, initially my mind went to like a flat surface area but you could have some topography changes in your landscape so it could kind of fit into different spaces as well so you might end up having, you know some different, excavation needs like essentially you want four to five inches of rock on top is that what it was at minimum think some sources said it could go 10.

Chris Enroth: 08:28

Four to we'll go say four to six inches 10 inches is so much.

Emily Swihart: 08:32

But he wasn't shy about saying that some of those some gardens did that which is so much much rock. Yeah and so the big argument I guess like why is my next is my question my first question like that's a lot if even if you're not excavating that's it's a lot to haul in so much gravel or rock you know pea gravel gravel whatever you're using as your your gravel type like why what what what is this garden designed or intended to do that the traditional gardens that we're doing just planting in soil are not doing because to me to justify those resources like we need to know why what is the benefit?

Chris Enroth: 09:25

That's a good question and don't, Ken are you or would you like to tackle that one?

Ken Johnson: 09:34

So so my thought I will admit when I first heard about this, I was a little skeptical. Maybe I still am about how how well this would work out. Just my with my experiences with gravel and mulch, we were putting those on much thicker. So the idea is that you've got this four to six inch layer of gravel and that when, you know, weed seeds and stuff land on it, either they don't germinate or if they do, the roots aren't getting down to the soil and they die. So it's you're reducing your your weed pressure.

Ken Johnson: 10:03

And some of the stuff I've read and listened to, you know, they talk about how you have very few weeds in here if you keep up on your your maintenance and maintain it like you're supposed to. I don't know. And if if you guys have dealt with gravel mulch, you know, that it it works pretty well the first couple years. But then as things debris blows in, plant material, soil, and stuff, as those spaces get filled up, then the weed seeds can germinate and you start getting problems. So that's kind of was my a little bit of my skepticism.

Ken Johnson: 10:38

But typically, we're not putting on gravel mulch four to six inches deep and probably not maintaining it like you would a gravel garden.

Emily Swihart: 10:48

Yeah, that was my understanding. I was going to offer to also kind of answer the own question, which is the biggest reason that I heard cited for why this is an advantage over other gardens is that weed suppression. They're not if they're germinating there's not the nutrients it's a dry, substrate that they're in there's not a lot of moisture being held in that gravel and so they'll you know there's not nutrients there's not moisture there's lot of air they even they cannot survive they don't have enough energy to develop a root system deep enough to go to that soil you know six inches below that gravel substrate. I did also have the same concerns Ken you had with like organic matter build up in there but then I also was reading that some I think was at Chanticleer their garden, they mixed in some organic matter and sand into the gravel so I don't really understand that methodology. I did also didn't look into it any more than just going that's a different than the prescription that I've been hearing over and over so, they might be testing something out, because because this is kind of a new method of gardening but the weed suppression was the biggest argument and then that kind of led into lower maintenance.

Emily Swihart: 12:04

And the lower maintenance had some caveats where it was like oh you have these like deep rooted prairie plants and I think we'll talk about the plants that go in here but that was we kept being excited as these deep rooted like prairie plants or native plants for the most part and I just kept thinking mine are doing fine in the soil like I don't need all the gravel so that like I kept thinking they will do well here but is it necessary to haul all this in so I don't know maybe we should edit that out being a little negative. Just am skeptical like it just seems like you're hauling in a lot of rock and that's pricey and that are the rock mulch I'm still skeptical about. Do you have anything to add make me make me a believer?

Chris Enroth: 12:53

I am horribly biased against rock mulch. When I did landscaping, that's like what everybody wanted. And I have pushed plenty of wheelbarrows full of rocks. It's I'm not really a fan of it. In our education, I feel like our background, it's always been about soil improvement.

Chris Enroth: 13:19

How can we manage soils? How can we improve the health or the quality of our soil? In gravel garden, it goes the opposite direction. It is saying, how do we make this growing environment more harsh and inhospitable to most plants? And there is going to be a select few plants that we'll talk about that are more drought tolerant, that can survive better in these harsh conditions.

Chris Enroth: 13:50

And it just kind of goes backwards a little bit than what what my brain was trained to do. Now there is a difference between the rock mulch that I pushed in that wheelbarrow all those years ago and the gravel used in these gravel gardens. So specifically, they're looking for a quarter inch to three eighths inch size gravel. I think, Jeff and Teresa, they recommend a they they prefer like an angular stone as opposed to the pea gravel type, which is rounded. But a lot of gardens in their book do incorporate pea gravel into their gravel gardens as well.

Chris Enroth: 14:35

So, and it might be more of an aesthetic choice. So the pore space that's created by that smaller gravel size also does play a role in how much organic matter or debris can be caught up. With the larger stones, can get big leaves and things that get caught up in there. But with the smaller stones, especially the angular ones that kind of lock together, you get less it's more difficult for larger pieces of organic matter to to get into there as opposed to the larger mulch, rock rock mulch, I'll say. So yeah, that's that's the big distinguishing feature.

Chris Enroth: 15:13

But I agree. We live in flat land Midwest. There's not much rock sticking out of the ground where we are. So you got to truck this in or you got to mine it somehow. So it's a carbon footprint thing too.

Emily Swihart: 15:30

To that so that question was asked during one of the interviews that I had listened to and it was kind of about that carbon footprint like offsetting it and the response was, I'm summarizing, was that there's a lot of, input into our gardens, our traditional gardens and so this like upfront one time input, the argument was made that it offsets that ongoing need for input, over time. The way I garden personally, I don't know that that would play out, by the numbers. You know like one of the, citations was on wood mulch. Well I use use wood mulch on my garden and I apply annually and it decomposes you know it's, but I get it from our compost facility no trees are being cut down to harvest the mulch that I'm using. It is building soil health which which is something that I believe to be a good thing, and want to do in my landscape and I'm using very similar plants actually with the well a lot of the plants that he was citing I'm using in my landscape and so in some cases I do suppose that maybe the the balance sheet would work out in terms of that carbon offset at the front end if in fact it was constructed the right way and it was in fact lowering maintenance input and you were maintaining your garden in a way that required a lot of carbon input.

Emily Swihart: 17:13

Know it's all individual, but that I just I kind of wanted to address that carbon conversation you guys please feel free to add to it I just I had that same thought where was like man you have to have like a dump truck like hauling in mulch after it's been you know excavated.

Ken Johnson: 17:32

I think if you would compare it to a I'll say, your typical landscape where you're going and buying bagged mulch from a garden center Yeah. I think that that probably adds up pretty quickly.

Emily Swihart: 17:47

Okay.

Ken Johnson: 17:49

Then, you know, if you're depending on what you're using to to maintain that, if you're using gas powered

Emily Swihart: 17:54

Yeah.

Ken Johnson: 17:56

Equipment and stuff. And I think if you think of the typical, whatever typical is, way these things are maintained. You know, I could see how that would you've got your kind of your big cost upfront carbon footprint wise compared to spread out over five, ten years, whatever it does. And I can see that evening out over time.

Chris Enroth: 18:24

Could we describe how plants are installed in gravel gardens to give people maybe a complete picture of, like, all right, we got five inches of gravel. We're just like putting plants in there. Like how? So we've we've we've excavated the soil, we've replaced that soil with gravel. Now how do we put those plants in there?

Chris Enroth: 18:43

And how do they survive when the weeds don't? Would one of us like to describe the planting process and how that works?

Ken Johnson: 18:52

So so my understanding is basically you get your gravel, then you unbury it. You pull it up back, take your plant in a pot, place that pot on top of the soil, put the gravel back. So you're not actually putting it in the soil. You're resting it on top of the soil, and then you're watering to get those roots to go down into the soil. And then they become established.

Ken Johnson: 19:18

And in theory, you don't have to water anymore unless you got a, you know, a drought or something going on. But yeah, not like know, it was not like your traditional I dig a hole, put that in the ground from the soil back up. You're placing that on top of the soil and your your gravel is covering it instead of soil.

Emily Swihart: 19:39

Yeah. Yeah you're treating like the crown is at the top of the gravel and so the first five six inches of your root mass is in that gravel substrate before it hits the soil. And you hit on an important point Ken, there's a lot of watering maintenance that needs to be done to establish this. That was shared freely in the literature in the interviews was you have to establish these plants. They have to be able to get their roots down into that soil substrate before they are capable of withstanding this type of system.

Ken Johnson: 20:19

So I assume you're using probably a little bit bigger plants just so they have a bigger root ball or you wanna get stuff in deeper pots so you can get it down far enough.

Chris Enroth: 20:28

So the suggestion was to they they did they wanted people to stay away from things gallon size or even greater. They're talking three to four inch pots, maybe even plugs. And that the reason specific reason why escapes me I think it is the amount of weed seeds that are actually found in potting, potted plants that you get at the nursery. They kind of wanted to limit that. And a lot of the projects in this book, they almost like rootwashed their plants that they put in the ground.

Chris Enroth: 21:05

Soaked them or they completely rinsed off the potting mix or they took off the top couple inches of potting mix, which that was something I learned. And I will be doing that from now on. I will be taking off the top like two inches of potting mix on all plants I bring home from now on just because there's a lot of weeds in that top layer.

Emily Swihart: 21:25

Yeah, I thought that was an interesting tip that could be applied to everything. Thought oh yeah sure that makes a lot of sense so, I agree I'm gonna do that but, yeah it was it was also, cited for just for cost. You know bigger plants, cost more money, digging out that gravel you know a bigger hole can be a little bit more labor intensive just at the planting time. But yeah I think that especially with some of these plants that we're we'll be talking about they are good candidates for starting as plugs they're not overly sensitive when they're being transplanted whether they're into a gravel garden or into a, you know they're native plants that have pretty robust root systems, kind of from the get go and they're raised to have robust root systems like that's we're not pushing flowers in that first year of growth you know like your annual flowers and you're buying you know for bloom count when you're buying native plants and those are mostly what we're buying for our gravel beds everybody understands that we're going for the roots. But that was a good good go back.

Emily Swihart: 22:38

Okay now what we did jump ahead we're jumping around and I'll apologize to our listeners like we got really excited about this topic and we just dove right in. Maintenance wise also so we've talked about how it's gravel, how you have to water in that first during the establishment period. I'm going to say first year, I think it was some of the the advice was a shorter time period than that but it all depends on weather right if you just if it dries up in the summer if you have hot you know windy site and the gravel is going get warmer than traditional like wood mulch. So you might need to apply more supplemental water. Fertilizer though, so I had heard comments and I think across the projects that were kind of looked at and Chris maybe they speak to this in the book I don't know.

Emily Swihart: 23:33

Some of the sites did find that they needed to occasionally as the site matured and advanced apply some additional fertilizer to the plants. Did either of you come across that advice or was that referenced in the book at all?

Chris Enroth: 23:51

Not, it was referenced in the book in that the plants selected may not do well if they provided supplemental fertilizer. And so no, that's an comment then that, I mean, I can definitely see it because we're creating a low nitrogen environment, a low nutrient environment. And if you want your plants to get established, you got to give them a little boost there of nutrients to get those roots in the ground and to get those leaves photosynthesizing. Kinda makes sense that you might need to supplement with some fertilizer there.

Ken Johnson: 24:29

Yep. I think I saw something somewhere that maybe they to some extent, it may be a good thing that it's a little less depending on what your soils are like, a little less nutrients because the plants don't get maybe quite as large and unwieldy Mhmm. Shall we say as they were if you had straight soil, you're planting them. And so could be a benefit or But a

Chris Enroth: 24:55

one one comment was that these gardens, you could put aggressive native plants, and they wouldn't take over. Like it won't it's not going to be as bad as putting them in like a prairie loam soil. If you try to do a backyard prairie garden, you put a cut plant in there and in three years it's all cut plant. So from one of these chapters I read, they liked it because they could put in some of these more aggressive native plants and they wouldn't be spreading and taking over things as they would in the normal prairie soil.

Emily Swihart: 25:31

I suppose the same thing would apply to like those annual weeds as it would for our more prolific re seeders for native plants you know like I'm thinking of like purple coneflower like those seeds will germinate everywhere but perhaps in this style of garden the same effect is that they might germinate they just don't have enough energy or enough time to get down to that soil to access those nutrients and they die out, kind of naturally. Is that what the theory was?

Chris Enroth: 26:05

Yeah, yep there's just too much air in those pores in that gravel. And those roots can't overcome that barrier to get to the soil. Now, it comes to maintenance, I read repeatedly that when it comes to weeds, the worst part's going to be around the edges. Because that's where you're going to have probably the closest access to soil for some of your plant roots. And that's also why having that edge, that lip, that five to six inch is so much more important on the edge of that gravel garden.

Emily Swihart: 26:49

So we do keep like referencing like native plants we keep saying like deep rooted plants like can we spend some time on on that because not all native plants are created equal this is more of a dry garden so some of our wet loving species are not going to be recommended for gravel gardens. Many of the plants that I saw referenced, the native plants, were grasses. A lot of our native grasses were referenced quite a bit. There were some forbs but, kept seeing things like prairie dropseed, cynotes grama, little bluestem, know like a meadow kind of look like just full of you know kind of some of these grasses and they are more stunted like you said Ken so, something to keep in mind. It was also interesting, there was discussion they're non native but for bulbs being incorporated into these beds and that, you know a lot of our spring bulbs like we have troubles or they can succumb to rot because we sometimes have soils that are too moist and so if you have a bed that is intentionally designed to not have, moisture kind of up in that you know top layer then it's going to be a little bit more conducive to planting these bulbs.

Emily Swihart: 28:12

I'll say this raised more questions for me because a lot of our bulbs outside of narcissus are, like a lot of nutrients you know they're like heavy feeders so like but then we don't have a lot of I got all confused by what what was happening with the spring bulbs but, they seem to do well in some of the gardens. So native grasses and bulbs is what I'm there are some forbs, like that's a super generalization. Don't know, like Chris, are there plant lists in there? Are there other plants that we should be considering?

Chris Enroth: 28:49

Oh, yeah. Each chapter, each garden, they highlight a lot of the main plants that are in each garden. Bulbs are very popular. I see a lot of the giant onions, like those types of bulbs. They seem to be very popular.

Chris Enroth: 29:10

And they look amazing in these images. I don't know, Ken, if you remember when we did the crocus episode, there was that grower in Poland, I think it was. He kind of created these gravel gardens for his crocus. It sounded similar. He would excavate the soil because I think we both commented like, boy, that sounds like a lot of work.

Chris Enroth: 29:34

And then he would replace it with sand or like a fine gravel or something. And so I didn't see crocus mentioned in here, though. I did see grape hyacinth mentioned and a few others. But in terms of some of like the species listed, some favorites of mine are definitely in here. So our Echinacea pallida, which is the pale purple coneflower.

Chris Enroth: 30:01

I like that one better than regular purple coneflower. I don't know if either of you have an outlook or viewpoint on echinacea, but that one's one of my favorites. And it's highly successful in gravel gardens, it seems.

Emily Swihart: 30:17

I have that same opinion. I don't think we use palette enough. Think purpurea is too, they've had their time.

Chris Enroth: 30:27

They've become pretentious.

Ken Johnson: 30:30

Yes, too popular. Yeah,

Emily Swihart: 30:32

just the bloom, I don't know the bloom of pale is really it's unique and maybe it is just because purple is so popular but

Chris Enroth: 30:40

yeah

Emily Swihart: 30:41

I agree.

Chris Enroth: 30:43

That's and then some other fun ones so we have Royal Catchfly is one that I saw on a couple different ones. Rattlesnake Master seems to be a very popular one that that pops up in a lot of these. Catmint is is another one of those like a cultivar Walker's Low or something like that. And lots of yarrow seen a couple with yarrow in it. Black eyed Susan seems to be quite popular.

Chris Enroth: 31:13

Bergamot or the bee balm, salvias quite popular. So, you know, we've incorporated a lot of good native plants in here, drought tolerant native plants. Because we are putting we're creating this harsh environment. And we need plants that can that are a bit tougher, that can survive that. I did note, in one chapter, somebody there was like, it was like a question is like, is this good for rain gardens?

Chris Enroth: 31:44

Could we be catching rainwater in here? And it said no, because a lot of sediment comes in with water runoff. And the biggest thing we're trying to avoid here is sediment. Any type of organic matter, anything that a weed seed could gain purchase in this case. And so, you know, we're staying away from maybe more rain garden type plants.

Chris Enroth: 32:10

But many of the native ones that we described, they can tolerate a little bit of extra water for a little bit.

Emily Swihart: 32:21

Can we is there more to say about the gardens? I've got questions about the maintenance like to that point where we're keeping organic matter out and then like we've referenced our experience with gravel or rock mulch like can we talk about the maintenance of these beds because it's a little different but I don't want to move us along too quickly. Else to say Go about the ahead.

Chris Enroth: 32:44

I only have one more thing I think about well maybe two more things but I there was a little differences in spacing of the plants. So in my mind, and Emily, you're you're there to where we're about to do rain garden installations. And we're doing this matrix planting design, which is really dense. It's a dense spacing. In one chapter, I wrote this down, it says they're spacing their plants to mimic spacing in a dry environment where plants typically only cover 50% of the surface.

Chris Enroth: 33:19

So if you've been hiking and maybe more of an alpine type area or a rocky type area, there's a lot of rocks and about half of them are rocks, half of them is plants that of that surface area. However, when you look at the the Texas case study here that has, oh, what's his name? Doctor. Jared Barnes, his name?

Ken Johnson: 33:44

Yes.

Chris Enroth: 33:46

So he's he's got a gravel garden project in here as well. And they did a dense spacing. Because in that Texas heat where that garden is located, they were trying to get plant cover over the gravel over the rock to shade so it wouldn't heat up so much in the in the hot summer months. And then there's another chapter that talks about how do these native plants do so well? Because doesn't rock get hot?

Chris Enroth: 34:11

Well, then it's that says the gravel is so thick, that the soil underneath of it never heats up to that point that that top few inches of gravel gets to. And so the plant roots stay cool. And so the more I read this book, the more I was like, well, depending on your region, you might do this differently.

Emily Swihart: 34:34

Yeah, and I don't think we mentioned either about they are full sun. So like I had heard about you know the kind of different variations of the parenting schemes when you are more southern and your temperatures are going to be warmer for longer. But traditionally they're not shaded they're not because that's the organic matter that's going be introduced like trees we love them but they do drop a lot of leaves and a lot of debris and so in a garden design to avoid having a lot of organic matter in it trees are not going to be ideal. Yeah I heard about that the type planting is it might also possibly just be an aesthetic preference especially in like northern climates. You could certainly have, you know 50% plant cover of your garden but I don't know that it would hurt anything to have more in there.

Emily Swihart: 35:31

Maybe water use a little bit but if they're going down deep and you know like once it's established going deep into the soil I don't know the water competition would be so much.

Chris Enroth: 35:42

Some people they did talk about that aesthetic choice too like you're trying to break maybe that habit of every plant in its little little spot in the landscape, and they don't touch each other. And and there was one project in here where it was sort of like, yeah, we were trying to, like we're fighting that that aesthetic, that that particular person wanting the plants to be in their own little spots. And there was another one where it's like, the client said, I really just like the gravel. I like the way it looks. And so they wanted to see it.

Chris Enroth: 36:15

So they probably had some really pretty gravel. A lot of the gravel, not all of it, is quartzite. So an angular stone can be colorful depending upon the source. But, it's, yeah. That I I think that's, it can be aesthetics.

Ken Johnson: 36:37

Let's say you're you're less dense planting, that's less gravel you have to dig through to plant stuff.

Chris Enroth: 36:43

It's true.

Ken Johnson: 36:44

Which I can't imagine is particularly enjoyable.

Emily Swihart: 36:48

Mhmm.

Chris Enroth: 36:50

Well, Emily, you you mentioned trees. Trees are good, but trees not good here. So yes, gravel gardens don't go underneath trees. But if we're creating these gardens, their plants do grow in gardens. We get debris from plants.

Chris Enroth: 37:07

So what about maintenance? We're gonna get plant debris coming from the plants growing in the garden. What do we do about maintaining and keeping that debris out? What's what's the solution for that when it comes to gravel gardens? It's not chop and drop, is it?

Chris Enroth: 37:22

You can't do that here.

Emily Swihart: 37:24

It is super not chop and drop. It's the opposite of it. I saw it was it was pretty basic maintenance which was to use a leaf blower like an electric leaf blower, to remove organic matter. The benefit is with gravel versus like a wood mulch is that it's going to be a little more dense and so you might not blast it all over you know you could use maybe a little bit more gust, to blow off some of that organic matter has fallen down like leaves and the smaller debris. I saw that you want do that kind of throughout the season even, if you can spring it it's said to do it in the spring and the fall, but in my mind like as if your plants are spaced farther apart like and it became an issue you probably could do that throughout the year to keep that debris off.

Emily Swihart: 38:19

And then cut your plants back in the spring and remove them from the site. If you're concerned about insects you can take those to a different location in your yard, you don't kind of let everything over or emerge in the spring but like that's that was kind of the kind of the two things it was like blow or rake out any of the organic matter that has fallen and then physically remove any organic matter that might fall.

Chris Enroth: 38:56

From the book it seems like a lot of the testimonies say like that's all we got to do in the spring is we got to remove last year's growth, blow off the garden, get all organic debris off of there. And it's good for a year till we do this next year. So that maintenance the level after it's installed and all that seems pretty, pretty easy. But I don't think it's that simple. I don't know.

Chris Enroth: 39:27

I don't know. I because I do you guys see in your mind? Because we deal a lot with just the everyday person. And not everybody. Some things happen in our lives where we can't clean up the garden in the spring.

Chris Enroth: 39:44

What happens then? And the book, I looked all over in this book, what happens if we have to rehab this? Or what happens if we have to get, if we do let too much organic debris there's no commentary on that.

Emily Swihart: 39:59

Yeah I had that same question I thought well like in theory this does sound great. At botanic gardens when you have a staff with a dedicated schedule for maintenance. But yeah Chris I live a similar life to you which is we have good intentions. Ken I'm gonna group you in here too like you're one of us. We all have good intentions we've shared it over and over then life happens or the calendar moves too quickly you know and it can be yeah I did question that I thought well like with, some of our, pervious pavement systems like you can vacuum it to clean it out you cannot vacuum pea gravel I don't imagine that would go well.

Emily Swihart: 40:45

So I don't know how you would rehab I don't know if it does just decompose and because this we should also say like there are some phenomenal examples of this this isn't just a theory like this has been put into practice and there are some phenomenal across the country that we've seen, and you can look them up online encourage people to kind of peruse and if there's one locally to you go see it. We've seen one I don't know that we realized all that we were looking at one but we saw one in Ames a number of years ago beautiful public garden so I think yeah like what happens when life gets away from you does that organic matter just kind of wash through like as it decomposes and go into the soil substrate? Don't, is it self cleaning? That'd be amazing but I don't know if that works. So I'm just rambling now because I'm like how does this work like in my brain it's like I I get the theory I love the idea of, having something that would work in this way I'm just I need to see it to believe it, maybe do it to believe it.

Emily Swihart: 41:57

I don't know.

Ken Johnson: 41:58

I think my big hesitation would be what if you don't want it anymore? Now you're digging out six inches of gravel.

Emily Swihart: 42:11

You better have some big burly friends.

Chris Enroth: 42:13

Mhmm. And that's why if you would do if you would install this, I would go with the angular stone as opposed to the pea gravel because a secondary use for that angular stone is you could build a patio on top of it. Because the angular stone compacts, pea gravel does not. It's always good to think of end of life stuff for for gardens, even with the rain gardens. Emily, I'm thinking about, well, what happens if the people no longer want to maintain it?

Chris Enroth: 42:44

You got to come up with like, this is what happens after that. And you did I love I didn't realize that when we were names we were looking at a gravel garden at was it Ryman's right?

Emily Swihart: 42:58

Raymond Raymond Raymond Gardens. It's a name, so it's Ryman.

Ken Johnson: 43:06

Okay.

Emily Swihart: 43:07

Yeah. It's

Chris Enroth: 43:07

capital. Ryman. Yes. And there's really beautiful examples in this book. There's one in Lamont, Illinois.

Chris Enroth: 43:15

I read there's some in Wisconsin. Obviously, Jeff Epine was the horticultural director at Obert, Obert,

Emily Swihart: 43:25

Obert,

Chris Enroth: 43:25

Botanic Gardens. And, and so but there are, I feel we're so negative. Are we really negative today? I have one positive thing to say. It's I'm gonna start it with a negative thing.

Chris Enroth: 43:42

So Cashion Schmidt, they he did a garden here. His garden was in Weinheim, Germany. And he is a famous plantsman known around the world. And he says, quote, it doesn't make sense to install a gravel garden on a nutrient rich, loam, heavy loam soil. And we have beautiful loam soil here in the Midwest.

Chris Enroth: 44:07

So that's where that's where my brain is fighting. But then they go on to talk about these civic projects where they're in these planting these parking islands. These are terrible spots, horrible soil. Post development type soils. It's just terrible subsoil.

Chris Enroth: 44:29

Yeah. Rip that stuff out. Put in a gravel garden. That makes more sense to my brain than taking some of our wonderful Illinois topsoil out to put in a gravel garden. So some of these public works projects where there's been a lot of construction happening and you need like a roundabout island planted with something beautiful, yeah, a gravel garden, which they have an example of in this book.

Chris Enroth: 44:59

I think that would be a great use of this style where we are going into soil or or a situation that's already not not good for plants. So let's create something that's lower maintenance for maybe our our staff and and and can create something beautiful still.

Ken Johnson: 45:21

Yeah. I mean, probably came across as negative. But, I I mean, after listening about it and reading about it, you know, it's kind of intriguing. You know, I'm tempted to try it, like, along my driveway where I've got some rock anyway, and it's not very wide, which may be an issue because it may be only two or three feet wide between us and the driveway and the property line. But maybe trying something like that.

Ken Johnson: 45:46

So then if I am tired of it, it just turns into driveway when I'm done because we've got a gravel driveway. So but it's limestone, so I don't know if that would you know, how that is that gonna affect the pH and to an extent where that's gonna cause new problems.

Chris Enroth: 46:05

Good point. A lot of the gravel so limestone that we have here in Illinois is soft and chalky. The gravel in these gravel gardens, they're all, like, very hard stone gravel. So they don't they don't change the ph like our chalky limestone does.

Emily Swihart: 46:26

And they wouldn't kind of like break down like over time with some of the activity of the root growth like limestone is especially some of it can be really crumbly and so it can break down. Yeah I guess I'll just chime in and say I don't maybe we came off as negative I think, skepticism like it's a new system we do have past experience that we're drawing from with our you know experience with rock mulch that's kind of what we know and so this is not rock mulch in the way that we know it but that's that's our reference point and so I think it's okay to kind of question like well how does this work as compared to what I do know. We do have you know for the most part most of us are blessed with some of this like dark rich loam soil nutrient dense. You know we live in the Midwest and so, that is our baseline. We're all midwesterners by rearing you know like it's what we've known for our whole lives and so I think it's okay to to approach things skeptically.

Emily Swihart: 47:33

I think we should maybe approach everything we're doing skeptically. Gravel gardens just happens to be the topic of the day we get to you know question and and I do believe that there's a place. Like your point with those like urban you know environments with heavily constructed environments maybe with sites that we're trying to you know like mitigate. I can see how this could be an application for those sites like all of our gardens. Like rain gardens don't belong everywhere.

Emily Swihart: 48:06

Prairie you know like some of our big prairie gardens don't belong in certain places. They eat houses you know plants get so big. And so you know right plant right place maybe it's right garden right place. But super interesting concept. I do want to do some traveling and make a point to go intentionally see these gardens, study them more, kind of analyze with a more keen eye rather than more of a cursory viewing.

Emily Swihart: 48:36

That's what we did in Ames. I want to go to Ulbrich, you guys want to go for a road trip maybe sometime?

Ken Johnson: 48:43

Let's do it.

Emily Swihart: 48:44

Because Ulbrac has four of them. I think there's four gardens there and so we could really justify the travel.

Ken Johnson: 48:51

Part two.

Emily Swihart: 48:53

Yeah.

Chris Enroth: 48:56

I And Ken, it sounded like you were intrigued maybe along the driveway. Emily, you think you would? Would you put in a gravel garden at this point, you think? Or first, you you maybe you don't have to answer that. That that's maybe the we shouldn't ask ourselves that question.

Emily Swihart: 49:11

No that's okay. I don't I'm not opposed to it. I love to experiment. And so I if the opportunity presented itself where I thought it was an appropriate application I absolutely would pursue it. And some of the advice that I kept hearing over and over again was to start small, and so that might be, you know what I look for.

Emily Swihart: 49:35

Maybe I you know partner with some master gardeners who are also curious about you know these different types of systems or some of our municipal, partners might have a site where I could you know see if they would be curious about doing some experimenting and education, with this. So personally I don't really have a site I live in corn country like I have I have nice soil and I sorry for everybody who doesn't like I'm so blessed by it and I do know what I have and so no I will not be excavating my really nice soil and putting in gravel. But I am not I'm not opposed to it. I've been convinced that it's something worth trying and exploring, as an option.

Chris Enroth: 50:17

Ken, put it along the driveway, you think?

Emily Swihart: 50:20

Do it.

Ken Johnson: 50:21

Maybe. If I get motivated to move all that gravel.

Chris Enroth: 50:26

I'll bring my shovel.

Ken Johnson: 50:28

Yeah. Make a video.

Emily Swihart: 50:29

We could do a good growing outing.

Ken Johnson: 50:32

Are you gonna put one in, Chris?

Chris Enroth: 50:36

If I had a spot 100%, I would totally put one in. I am I am just I'm just curious. I just wanna know I I like to try all the things. And this intrigues me enough that I'm like, I want to try it. I want to see what it's like.

Chris Enroth: 50:52

But I would totally start small. I still have a spot. I have too many trees. I'm managing debris constantly. Anyone who's ever had a tree over a patio or driveway, you know, there's always stuff falling from the tree anytime of year, summer, winter, spring, fall.

Chris Enroth: 51:10

So

Emily Swihart: 51:12

Like shade. We love the trees.

Chris Enroth: 51:15

We love them. We love them. Gravel gardens don't, I guess. No. No.

Chris Enroth: 51:23

Well, that was a lot of great information about gravel gardens. The Good Growing podcast production of University of Illinois Extension edited this week by Emily Swihart. Emily, thanks so much for hanging out, chatting about the gravelly gardens that we're all learning about. And I guess that people want to learn more. Jeff Epstein, he's just selling his book now.

Chris Enroth: 51:44

And so he's doing all his media stuff. And I think, yeah, that's where we all kinda heard about this.

Emily Swihart: 51:50

Yeah. No. Chris, this was a great great conversation. I love when there's new concepts and new kind of innovative ways to, engage with the landscape. And it's curious.

Emily Swihart: 51:59

Like, this this piqued my interest. And so, I do. Let's travel. Let's go see them, observe, put them in when we can. If anybody's listening or viewing, if you have one experience with it, know of one nearby, like, please, you know, drop us an email.

Emily Swihart: 52:13

We would be very curious

Chris Enroth: 52:15

to hear from you. So And, Ken, thank you for hanging out, chatting about gravel gardens, and donating your very own driveway for our Good Growing Experiment of gravel gardening.

Ken Johnson: 52:28

So we'll get a date on the calendar, eat your Wheaties that day, and we'll get to work.

Chris Enroth: 52:33

Got an equipment rental site in Jacksonville by chance?

Ken Johnson: 52:36

We do. Alright. Even better. I'll make my children help too. Let's do this again next week.

Chris Enroth: 52:46

Oh, we shall do this again next week. We're gonna be chatting with state climatologist Trent Ford about, well, this summer and this winter. What to what's happened and what will happen. So look forward to that. Listeners, thank you for doing what you do best and that is listening or if you watched us on YouTube watching.

Chris Enroth: 53:05

And as always, keep on growing.