watering the garden (not the plants), a 101 with daryl beyers
SUMMER: IT’S WHAT I refer to as the season of dragging hoses, and for me at least this year, the fact that it seems to have stopped raining with any regularity or measurable impact is making it worse. This is the season when we must all pay strict attention to watering, but how, and how often, and what to give our attention to most and why?
I talked about watering best practices with New York Botanical Garden instructor Daryl Beyers, author of “The New Gardener’s Handbook” (affiliate link). The popular course that Daryl teaches at NYBG is called Fundamentals of Gardening. And now Daryl, who has more than 25 years’ professional landscaping experience besides his teaching role, has put all the fundamentals into “The New Gardener’s Handbook.”
Read along as you listen to the June 29, 2020 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on Apple Podcasts (iTunes) or Spotify or Stitcher (and browse my archive of podcasts here).
Plus: Enter to win Daryl’s new book by commenting in the box at the bottom of the page.
Plus: Links to his free Monday evening Zoom Q&A sessions; a webinar-style talk he’s giving online July 9 in the evening; his NYBG class online, and other “extras” (including the interview I did with him for “The New York Times”) are at the bottom of the interview transcript.
watering the right way, with daryl beyers
Margaret Roach: So welcome back, Daryl, how are you?
Daryl: Hi, Margaret. I’m doing well, I’m a little bit dry, but I’d like to get wetter hopefully someday.
Margaret: Yeah. Where’s the rain? You promised when you came on the show, you’d tell me how to make it rain.
Daryl: Well, my trick is to plant lots and lots of new plants, and then say a little prayer and hopefully it works out.
Margaret: O.K. So I loved in your book that you got to quote, you managed to somehow figure out how to quote, Leonardo da Vinci in a garden book. Do you remember that quote?
Daryl: I do remember that.
Margaret: “Water is the driver of nature,” you said—or you quoted him saying. [Laughter.]
Daryl: Yes. It was in the introduction, yeah. Well I mean, Leonardo knew a little bit about everything, basically, so I think he actually knew something about water, and watering in the garden as well. Because your garden will not grow without the proper amount of water. And it doesn’t mean that it always needs a lot of water, but it does mean that it needs some water.
Margaret: In the book there were so many factoids about watering to make me think about it differently. You talk about a 50-foot shade tree loses up to 60 gallons of water per hour. A healthy tomato plant will absorb at least, and release at least, 30 gallons of water throughout a growing season. I mean, things like that that you start to visualize how important it is. Can you tell us about the different functions of how water is used by plants during times of growth?
Daryl: Well, I mean it’s required for the metabolism, for pretty much all of their metabolisms, which is why Leonardo had it right where it’s the driver of life. And so what I talk about is several different aspects of it, first of all cell expansion. In other words, for the cells to divide and to grow water has to be present. Otherwise, it’s just not going to happen.
Also, the water that the roots are absorbing and bringing into the plant is conducting all the nutrients up in and around the plant, and distributing it throughout, so the vascular system is flowing because water is available.
This then in turn creates something called turgidity, which is basically the stiffness of the herbaceous parts of the plant. So your plant will stand up straight, the leaves won’t wilt, and things like that.
Water is also necessary for propagation to get that seed to germinate. And even for propagation techniques like, taking cuttings of plants, and even if you’re trying to do air-layering on a stem or something like that.
But even more importantly, plants will not photosynthesize without water. And photosynthesis is that engine that fuels the plant, because through photosynthesis the plant then is able to create carbohydrates, and water is one of the ingredients in that little chemical formula. Its CO2 plus H2O in the presence of sunlight and chlorophyll and you get sugars and oxygen as the result. And so water is part of that formula to start with.
Margaret: So when I began gardening, there was this conventional wisdom, probably folk wisdom or old wives’ tale or whatever we want to call it, that in the Northeast, the garden needs an inch of water per week. And it was as if it was some formula.
And you point out in “The New Gardener’s Handbook” that the needs for water vary due to not only the stage of life the plant is at, but to the weather, too. Like, if it’s really humid and so forth. And that having thinking there’s some formula can lead us astray, just like not watering can lead us astray, yes.
Daryl: Exactly. Those rules of thumb can be helpful to just get you thinking about it in the first place, but to garden with rules like an inch a week kind of thing. Gardening doesn’t really function like that; it’s not as cut and dry. There’s too many variables that work into it.
And one of the big pieces of the watering puzzle is to understand something called transpiration. That’s one of the metabolisms that plants have is transpiration, which is another… A little term that we like to use instead of transpiration is “plant perspiration.”
Daryl: In other words, your plants are sweating, just like people sweat, and they have pores on the undersides of their leaves. And they’re always releasing water vapor into the air whenever they are actively metabolizing. Whenever they’re photosynthesizing, or growing, or doing anything, they’re always releasing that moisture.
And they absorb all that moisture from the soil, and then they release it into the atmosphere, and they’re continually cycling that through. And that rate of transpiration is affected by a lot of different things. Primarily one of the big pieces is just the atmospheric and environmental conditions that are taking place.
So a very dry, windy, hot day that plant loses a lot of moisture because it’s releasing it out into the atmosphere; it’s sweating really heavily. A more humid day, or a cloudy day, or a cooler day, it will release a little bit less moisture. And so the rate is always changing, which is why that rule of thumb doesn’t always work because you could have different weather conditions based upon… It just depends on what’s going on.
So I take a look outside and I see it’s really humid, it’s really warm, but it’s not very sunny and it’s not very windy. So I got a good chance that my plants aren’t going to be losing a lot of moisture today because it’s just almost equalizes with that humidity in the atmosphere. And so I can probably get away with not watering and even though it’s really hot outside, they’re not losing so much moisture like they would, if it was really windy or if it was very dry. And so you have to play it; you have to play both sides of the court there and think about what’s going on outside.
Margaret: So you encourage us in the book also to think about watering the garden, not watering the plants. Can you explain that philosophy to me?
Daryl: Yeah. it’s almost a conceptual idea that then really will help a new gardener understand what it is that they’re trying to accomplish. And so we talk a lot about like, “Well, I got to go and water my plants, I got to go water my plants.”
And so it’s important to understand that you’re not really watering your plants, you’re watering the garden. And when I say you’re watering the garden, what I mean is you’re watering the soil. All the water that your plants use for their metabolism, for their photosynthesis, for cell expansion, conducting nutrients, all this stuff—it absorbs that water from the soil through its root system.
So you can spritz and spray your plants and cool them off that way or they actually like that sometimes, it’s not a bad thing to do. But that’s not moisture that they then absorb and use in their metabolisms; they don’t really use that water in the same way.
All the water that they use and need comes out of the dirt, comes out of the ground. And so ultimately what you need to do is you need to water the ground, and then the plant can absorb that moisture and use it for all of its functions. It also helps avoid overhead watering, where we get into fungus problems and other stuff like that. If you overhead water too much and actually just you’re sprinkling right on the plant too much, that can become an issue, too. But also you just need to charge the soil—you need to charge the soil with moisture to get it present for the roots to absorb it later on.
Margaret: And so then… The more organic matter we have worked into our soil as good stewards of the soil and organic gardeners and so forth, like the more compost, the more humus that’s in there. I would assume then that the soil is a better medium for collecting and then dispersing, so to speak—I’m using the wrong words, imprecise words—but dispersing this moisture to those plant roots.
Daryl: Exactly, exactly. So a plant root will not grow if there is no moisture present in the soil, so that’s another piece of the puzzle. Whereas, if that soil is dry the root itself… The cells can’t divide and grow into that dirt, so you’re never going to get expanding roots.
And if you remember from what we talked about last time, where we talk about balancing the roots and the shoots. So the stronger and more vigorous your roots are the better, bigger and brighter and happier the top of the plant is going to be. So the soil needs to have some moisture in it for these roots to expand.
And so what we’re always trying to do as gardeners and stewards of the land is to make our soil better. It’s the foundation upon which we grow our gardens and adding organic matter improves our soil in a lot of different ways. And one of the ways that it improves our soil is it increases the water-holding ability of our soil. It improves our soil structure, so then it can hold water better. In other words, it creates more air pockets for water then to get into.
The organic matter helps the water cling to the soil particles, it forms like a film around the soil particles—makes your soil a little bit more like a sponge and less like just a collection of marbles and sand and stuff like that. That’s what makes your soil spongy and holding water.
There’s something called field capacity, which is the amount of moisture that your soil can hold. And so you’re always trying to improve your soil so it has a higher field capacity, which basically means that’s the amount water that your plants get to use.
It could rain 10 inches, but if your soil can only hold a half an inch of that, it doesn’t matter how much it rains. And so it could rain on Monday, and if you have soil that doesn’t hold water very well, then by Tuesday afternoon you may need to water again. Whereas if you had soil, the nice, rich organic soil that had good, what we call field capacity and moisture holding ability, you probably don’t have to water till Friday. And then maybe by then it rains again and then you didn’t have to water again.
So I’m always trying to get gardeners to build up their soil so it holds water well and then they don’t become reliant so much on the summer of dragging hoses, right?
Daryl: They don’t have to drag as many hoses around because maybe you get lucky and it rains in time before things dry out too much. So you’re always working on that, trying to make the soil hold more water. And then the thing is, it also gets complicated because then it depends on the plant as well, the plants that you’re growing and that starts to mix things up again. Gardening is never as simple as it sounds, there’s just always an added wrinkle.
Margaret: Should we give up now? [Laughter.]
Daryl: No, no, part of it it’s all fun, it’s the whole idea.
Margaret: I know, I know. And I think I might have already made that decision many decades ago in my life here—she says, looking out the window at a couple of acres of plants [laughter].
So the other day the plants, the 25ish shrubs that were meant to come in April–that I ordered in the winter that were meant to come in April for a project that I’m doing, which is reclaiming the top of the upper hill of my property to not mow it anymore, and add more native things and let it be wilder and so forth to increase diversity. Those shrubs, all native things, youngish things but nevertheless a couple-of-gallon size to 5-gallon sized things nursery pots. Well, they arrived because COVID-19 had shut down the ability of the nursery to do landscaping jobs, to come and help dig all those things in. Anyway:
So dot, dot, dot, here we are a couple of months late, no rain has happened in forever, it feels like and it’s on the very top of the hill where I don’t have irrigation water. So anyway, so here I am, and I think I’m was reminded of your lesson in as the two guys from my favorite local nursery and I mud… You call it “mudding in” the plants and I call it “puddling in.” So newly planted things, we need to really give them a good start. So quickly can you tell me about that, that process?
Daryl: Yeah. This is when we start to distinguished between how a commercial landscaper might install a plant. “Install,” another word—and how a gardener actually plants a plant. So gardeners do it the right way, so I’m always trying to teach the gardener the right way to do it. In other words, we’re not in a hurry, we’re O.K. with getting it done right and taking our time and doing it the right way. We’re not trying to make a certain amount of money an hour, that’s what a landscape company does, and so they won’t do this technique.
And the technique of mudding in or puddling in (above), is basically you dig that hole for the plant and then you take the plant out of the container or whatever, however, it was packaged when you received it. And you put it in the hole and you water the rootball right in the hole, and you actually fill that hole with water.
I’ll drag around a hose with a spray on the end, like a water breaker at the end, and I use one of those really light cloth hoses, so I’m not wrecking all the stuff that I’m crawling around in, and I just fill that hole up. I turn it on and then I fill that hole up with moisture, you just water.
And then I start backfilling, and then I’ll backfill a little bit and then I hit it with water again, to actually help that backfill settle down around the root zone. And I keep doing that and basically what that means is you’ve completely saturated and got all that water around the root ball up to that field capacity thing that I was talking about. In other words, the root zone of that plant has got plenty of good moisture in and around it and down deep.
This is especially important if you’re planting bigger plants, because the danger of the landscapers’ technique is to plant the whole thing, plant in the ground stomp around the roots with their boots and compact this-
Margaret: A lot of stomping—not these people, but I’ve seen a lot of stomping. [Laughter.]
Daryl: A lot of stomping—don’t stomp at all. But they stomp around, and then they water it. And then they hit it for two, three minutes, and they think that that moisture is actually going to get down into the root ball.
Margaret: It’s not percolating at all.
Daryl: Doesn’t make it—never gets down there. This is your one chance, this is the thing, this is your chance. You have full access to the root zone of that plant. You’re looking at it, it’s almost like it’s on the operating table and it’s all open and now’s the time to do it, right? You want to do it once and do it right.
And so you soak that puppy in and then if you get it all nice and wet down there. And then you use the water to settle the soil, and then you fully charged all the moisture around that. And then that can sometimes last you at least the first few days of the plant’s life, it’s got plenty of moisture around it. And then after that you’re going to get into the cycle of that establishment watering.
Margaret: Right, right, right. So I think that’s really important for people to know especially, if they are going to be summer-planting anything. But in either end of the season, even in spring and fall when it tends in the Northeast, where you and I both are to be somewhat cooler and moisture, nevertheless to follow that process.
Daryl: Exactly. Even in April I’ll do it. But now it’s getting like, you definitely have to do it now; I wouldn’t… Because July and August are tricky months to be planting for sure.
Margaret: Well, you should’ve seen us [laughter], the bucket brigade-
Daryl: And now you just have to hope that it’d be so great if it rained. If you can get away with it, I like to tell people to try to time their plantings with the weather. And if it’s going to rain that evening or the next day, try to get as many things in the ground as you can.
Margaret: I totally agree and this was again, this was something—an April project that couldn’t happen legally until now and they had all these other things. I mean, no nursery is on any schedule right now; it’s a bit of craziness.
I want to complain now a few minutes [laughter]. I want to complain about how bad most of the watering equipment that’s available to consumers is, because I have wonderful hoses that I love, like made hoses better drinking-water safe and all that kind of things from a family out in the Pacific Northwest called Water Right [affiliate link]. And they’re great because they’re light and again, I have to drag hoses, hundreds of feet, and I’m one person.
So they work well for me but everything else I have to say, I’m really disappointed in the junkiness of a lot of the watering equipment, and finding a good hose-end sprayer. Not that I want to spray like I’m washing my car; I don’t want to deal with a plant like that. But what you were talking about before with the breaker on the end, one that lasts, that doesn’t leak. Sprinklers, a good-quality sprinkler I mean, it’s tough to find. What should I be looking for? Do you use sprinklers at all? Because I like to use an oscillating, or you call it a fan type of sprinkler.
Daryl: Yeah. They can be handy in spots. You have to be real careful that you’re not… That none of that direct spray is hitting plants because you can get some fungus problems and other stuff like that. But they can be really useful, especially if you’re trying to establish maybe some lower-growing stuff or just to keep a part of the garden a little bit more moist. Maybe the early vegetable garden before there’s too much foliage and things like that. Yeah.
The more durable, the better—and so in other words, the less plastic parts the better off. And so I’m a big fan of paying a little bit more, and buying the sturdier tool and the sturdier equipment and then it lasts forever.
Margaret: I wish I could find it. I swear, I keep wanting to say, “Where’s the secret source for the really serious professional stuff?” Because really it’s not so good, I used to always use a lot of Gardena stuff years ago. They had models that I really loved, but most of those have been discontinued. A lot of things have changed in manufacturing of everything probably.
Daryl: Yeah. Because Gilmore is a big irrigation company, right? What you might have to do is step it up a notch to the commercial-grade stuff, it’s like a lot of sense.
Margaret: I’m going to explore this, good idea.
Daryl: Yeah. If you want to buy equipment for your kitchen like, pots and pans and things like that. The best score is if you can get yourself into a restaurant supply. And you do the same thing, so you could go to like a landscape contracting company, that sells a lot of the materials and irrigation sets and things like that. They’re going to have the more durable stuff. For example, even with other tools like shears and things like that. You spend $150, you don’t spend $30, and then you buy it once and then you’re done. So same kind of thing, so I’m always looking for metal parts and durables.
Margaret: Metal parts, that’s a good tip.
Daryl: So I want it to last much longer, I don’t want to be buying a new one all the time, so that’s kind of it. Because as far as brands go, I mean they all have different lines. They have different levels and different lines, and explore that.
Margaret: In the last minutes I just wanted to ask you a quick question about drip irrigation. A friend helped me set up a set up in my raised vegetable beds a few years ago and I’ve been using it. Is there a rule of thumb on how often and what time of day, and put it on a timer and let it run for X or Y? Is there any guidance on drip irrigation? Are you pro drip irrigation?
Daryl: Drip irrigation is the one irrigation that I like, that’s the one that I am like all about. Spray heads, I despise spray heads—they just wreck your garden. Spray heads are for little patches of lawn and rotor heads or for the golf course, right? And drip irrigation is for the gardener and so-
Margaret: Soil, waters the soil.
Daryl: Exactly, and that’s why it’s so good, it puts the water exactly where it’s supposed to be, which is not all on the top of the plant on the leaves, but on the dirt around the root zone. And as far as the duration of how much to run and how much water to put down as far, we like to talk about gardening long and deep, not short and sweet. In other words, I would rather have you… I’m sorry, watering long and deep not short and sweet.
Which means I would rather have the irrigation turn on two or three times a week and run for an extended period of time, which you basically have to figure out based upon how big are the plants in there right now, what’s your field capacity, what’s the soil like, what’s the flow that’s coming out of the drip hose.
In other words, how many hoses do you have laid down? If you have fewer you need to run it longer, if you have more you can run it for a half an hour, say.
So I have a bunch of drip hoses around some new cedar trees that I planted this spring and I finally started needing to water it and I can run it for about a half an hour. So you do a test, your first run, you try it. Run it for 20 minutes, go out there, put your finger into the dirt and see how far it seeped down, and then make your changes based on that.
You’re much better off running it long and deeply instead of 10 minutes every day, I’d rather we have a half-hour every three days. Because what’s going to happen is the moisture is going to soak all the way throughout the soil and then the roots are going to go looking for it.
That’s the trick to the whole thing. The roots are going to go, “Where is that moisture? I want to find more.” And if it’s deep, then your roots are going to get bigger and then your plants are going to get bigger. Yeah, it all works out.
Margaret: Well, Daryl, I’m going to go out and drag some hoses, I’ve got to hang up on you now. [Laughter.]
Daryl: I’m just getting started, you got to make these an hour long.
Margaret: I know, two hours, three hours ago.
Daryl: All right, Margaret.
Margaret: Well, but I’m so appreciative of your help,, Daryl Beyers author of “The New Gardener’s Handbook,” and instructor of the Fundamentals of Gardening at New York Botanical Garden, which you’ve been doing online as well, yes?
Daryl: Yeah, yeah. It’s a Zoom thing.
Margaret: Yeah. All right, so good. So we’ll give people with the transcript to all the links, and I’ll talk to you again soon I hope. Thank you, thank you.
Daryl: Thank you Margaret, happy gardening everyone.
more from daryl beyers
- Daryl’s July 9, 2020 webinar with Berkshire Botanical Garden
- Free Monday evening Q&A (Zoom link and details on his website)
- Online Fundamentals of Gardening course at NYBG
- My “New York Times” story with Daryl on composting
- Our previous interview, on smarter composting
enter to win ‘the new gardener’s handbook’
I’LL BUY A COPY of “The New Gardener’s Handbook” by Daryl Beyers for one lucky reader. All you have to do to enter is answer this question in the comments box at the very bottom of the page:
What is your watering method, and how’s it going? Planning on making any changes?
No answer or feeling shy? Just say something like, “count me in” and I will, but an answer is even better. I’ll pick a random winner after entries close at midnight Tuesday, July 7, 2020. Good luck to all.
(Disclosure: As an Amazon Associate I earn from qualifying purchases.)
(Photo credits: All photos and illustrations from “The New Gardener’s Handbook,” used with permission.)
prefer the podcast version of the show?
MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its 11th year in March 2020. In 2016, the show won three silver medals for excellence from the Garden Writers Association. It’s produced at Robin Hood Radio, the smallest NPR station in the nation. Listen locally in the Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) Mondays at 8:30 AM Eastern, rerun at 8:30 Saturdays. Or play the June 29, 2020 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes/Apple Podcasts or Spotify or Stitcher (and browse my archive of podcasts here).