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Planthropology
Planthropology
113. Houseplants, Diabolical Weeds, and Fickle Figs- Winter 2025 Q&A
This episode is a delightful exploration of listener-submitted plant questions, offering insights into plant care, specific plant challenges, and the relationship between environmental conditions and plant health.
- Overview of the seasonal Q&A format
- Discussion on controlling bindweed and morning glory
- Humidity’s nuanced effect on plant health
- Benefits of indoor plants on air quality
- Recommended houseplants for low-light conditions
- Host reflections on wisdom and community in plant care
If you enjoyed this episode and want to dive deeper into plant knowledge, be sure to share with your friends or leave us a review!
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Planthropology is written, hosted, and produced by Vikram Baliga. Our theme song is "If You Want to Love Me, Babe, by the talented and award-winning composer, Nick Scout.
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What is up? Plant people it's time once more for the Plantthropology podcast, the show where we dive into the lives and careers of some very cool plant people to figure out why they do what they do and what keeps them coming back for more. I'm Vikram Blakey, your host and your humble guide in this journey through the sciences and, as always, my dearest friends. I am so excited to be with you today. It is winter Q&A time. You'll know that every now and then, whether it's once a month or once a quarter and it's going to be once a quarter, I'm going to tell you seasonally, we're going to do Q&A episodes and I solicit questions from social media. I get people to ask me their burning plant or education or whatever questions, and then I try my best to answer them. So we've got a good set for today and everything from actually a lot about houseplants, lots of questions about houseplants today, which is cool. So we'll talk about that. We'll talk about humidity, we'll talk about rooftop gardening and even just what do we do? What do we do? How do we do the thing as we go? What do we do? We'll talk about that too. So buckle up, grab your favorite house plant and give it a nice little pat on the head and get ready for episode 113 of the Plantthropology podcast, winter 2025 Q&A. Okay so, first off, as I went back and listened to that intro section, I said my name so weird I don't know how to feel about that my name I say it a lot. My name is Vikram Baliga, not whatever. I said through a mouthful of oatmeal or whatever. I don't know what happened. It was weird, it's okay, we're going to get through it. Okay, lots of questions today and I want to just jump into them, so I've got time to do all of them as we get to this episode. It's maybe a long one anyway, maybe short and we're gonna find out. Okay.
Speaker 1:So the first one is from my friend, rui, and if you have a chance to look him up, he makes some sick lo-fi dad beats and the work he does goes to promote wildflower conservation and natural conservation. He buys wildflower seeds and does a lot of great work. You may be hearing from him in the not too distant future. So Rui, on Threads, asked why is Morning Glory and Bindweed such a diabolical I'm editing a little bit here plant, a diabolical plant. I can't use some of the other words he asked. That's okay. It's a family-friendly show, rui. Anyway, why are bindweed and morning glory so diabolical? And that is such a good question? And it's actually for a couple of different reasons. Now, if you don't know what these are, I'm going to give you a second to pull out your phone machine and Google morning glory, okay. So now that you've done that and you've got a good look at how honestly very pretty morning glories are, let's talk about why they are so difficult to control. Now, both of these morning glory and bindweed which, by the way, bindweed is perennial morning glory Most morning glories in our part of North America or throughout North America, tends to be an annual.
Speaker 1:It's not very cold, hardy, it goes dormant, it dies back to the ground or it just dies out completely in the winter. So for most of the United States and most places north of the tropical regions of the world, it's going to be an annual plant world. It's going to be an annual plant. It completes life cycle very quickly and because of that it does a few things that give it really great survival mechanisms. Right, it's got some great strategies for survival and growing. For one, it produces seeds prolifically.
Speaker 1:Now you've probably seen there's these bright purple, red, other colors in between flowers and, quite frankly, they're gorgeous. They're beautiful flowers, really wonderful. However, they're so aggressive. So they partner a couple of things together. One, they pollinate and fertilize readily. The bright colors, the high nectar volume that they produce, the big pollen load actually is super attractive to a lot of pollinators. So they get pollinated heavily, they fertilize readily and their seeds actually have a surprisingly high germination rate.
Speaker 1:A lot of times when we find plants that put out these big seed loads it's because maybe the germination rate's low, maybe they need very specific conditions to grow, and so you get high seed volume but not necessarily a high germination rate. It's an adaptation, evolutionary. They are hedging their bets against the environment. They want to make sure that they're going to grow and survive and make more morning glories right. So you put out big seed volumes and sometimes that's because not all of them are going to grow. But with morning glories they actually have a fairly high germination rate. So what we see is if you have a morning glory growing out of fence, on whatever, they drop tons of seeds and you're going to get tons of little seedlings popping up.
Speaker 1:The cotyledons as they come up on. A lot of these species actually look like plants, with I don't know how to describe it exactly without showing you a picture, which is hard to do on a podcast but they almost look like an animal, like a two-toed animal with a cloven hoof, and they have parts that come out in these pronged sort of growth, and so you get tons of them that come up, and even if most of those don't survive, these plants can grow so quickly. They grow up things. They're really good at climbing and twining. So fence lines, trees, taller plants, your, your dog if it's real slow will readily serve as a trellis or a support structure for these morning glories. They get up in the sun, grow quickly, produce a whole bunch of seeds and continue on. So there's some things we can do to control annual morning glory, pre-emergence herbicides, just removing them as we see them, and even though the seeds can be viable for a while, they germinate readily. You can, over time, over a few seasons, get them under control. Now they can be spread by birds and different things, so that is another challenge here.
Speaker 1:Okay, so enter field bindweed, convolvulus arvensis. So this is a very pernicious weed in North America. It was actually in, I believe, the 20s or 30s, and I could be wrong about these dates. I think called one of the worst noxious weeds in the American West or in the United States. This is, like I mentioned, a perennial morning glory and if you've been driving on a college campus or anywhere and there's a bunch of shrubs that don't flower normally and you look up and you say I didn't realize, this shrub had tiny little delicate white, pink flowers on it. That's pretty, it is, but it's also probably field bindweed.
Speaker 1:This is also a plant that grows very quickly, very readily, climbs up things. So from an agricultural perspective it's going to grow up your crops, whether you're growing cotton or corn or soybeans or whatever tomatoes. If there's field bindweed available, it's going to climb those plants, it will shade them out. It can cause a lot of other problems, including just muddying the crop. Right. If you're getting leaves and stems and flowers and seeds from field bindweed that gets mixed in with your crop at harvest one, it can make it less saleable because you've got other trash materials growing in there. But also from a cleaning and management standpoint it can be a lot more challenging because you have to have a clean crop to go out. So it costs you time, costs you money, not great.
Speaker 1:The problem we run into here is that this is a perennial plant that grows aggressively and has a big, deep taproot. Taproot is an underground root, typically goes straight down, and it's there for carbohydrate storage, resource storage, nutrient storage for the plant, but also to help it find water. This grows in a lot of really dry climates very well, and so it's looking for water deeper underground. One of the issues we run into here is that this taproot has a large number of nodes or growing points along the taproot and if you leave those nodes intact, even if you remove the above-ground portions of the plant, it comes back from the taproot and over and over till you give up and move somewhere else. Right, it's a challenge. Again. There's a reason it's called one of the worst noxious weeds in the us. It is that it's aggressive, grows fast. It's hard to control.
Speaker 1:Some things you can do to get rid of field bindweed, practically speaking, is like any other perennial plant that goes dormant in the winter when we get into late summer, early fall. That plant is going to work really hard to store resources in that taproot so that it can come back the next year. So it has the energy it needs to start putting leaves up all of that. So if you're one that uses systemic herbicides whatever kind of herbicide that is timing is super important. I think where we go wrong is like we see the plant. It's like I'm going to spray it, we spray it and then it comes back. I'm going to spray it again and over and over, and then over time we can develop resistance. We can develop a lot of issues, but if we time our applications thoughtfully, we use way less chemical and we'd be way more effective.
Speaker 1:So around here where I live in the northern part of Texas, around I don't know Labor Day a little bit, after so late September into early October, as the temperatures are starting to cool down, as the nights are cooling off, that's really the right time to treat our perennial plants if we're trying to get rid of them. So if we're going to use a herbicide, spray it with our herbicide then Because what happens is it gets absorbed into the leaf and instead of all that growth coming upwards, where the chemical gets moved up into the above ground portions of the plant, it gets stored in the taproot and when that happens we can actually get really good and really effective root kill and so you may not get all of it year one, but over time you can really deplete that prevalence of that plant. You can deplete how many are there, and so that's an effective. I don't know that's an effective strategy you can use just in general. But a lot of people don't like using herbicides and I can sympathize with that If that's the case.
Speaker 1:There are some biocontrol methods. There are bindweed weevils that will burrow into the stem and chew it up, but they're hard to get. They're expensive. If you don't have enough available, the weevils will die out before your bindweed and then you know you're back at square one. You spend a bunch of money for it. Really, what you're doing is going through this battle of attrition with field bindweed.
Speaker 1:You want to deplete the taproot. Every time you see a little baby plant come up, you get rid of it. Every time it comes up, starts photosynthesizing, starts trying to store resources down in the root, you get rid of it over and over again and over time you can deplete that taproot and you can kill the plant. It's a lot more time consuming, a lot more labor intensive. It's a lot more work, but if you don't want to use herbicides, that's really your best bet is just mechanical removal as often as you see the plant, because what you're trying to do is not let it store carbohydrates in the root. If you can do this, in the fall it's even more effective, right? Because that's this critical growth period where it's gonna store all of its resources and if you can deplete that, then in the spring it's harder for it to come back up, more susceptible to climate and a lot of other things. But yes, they're diabolical. They're so hard to deal with. Morning glory and bindweed are really tough weeds to deal with.
Speaker 1:So Rui hit me with five questions and I appreciate that because I need content. But I think I'm going to save a couple of these, or one of these for sure, and answer it in a video here in the next couple of weeks, just for the sake of time. But there is a question that I wanted to answer on the podcast. It's really very interesting. So he says is it true that relative humidity being in the right range allows plants to grow better and makes them more resilient to pests and diseases? Is it like balancing the internal hydrological pressure with the outside atmosphere? I don't know. I just saw some things in the greenhouse and it's got me thinking that this is such an interesting question Because in some ways it's maybe counterintuitive. In some ways, I think he's probably right on here.
Speaker 1:Now, as temperature and relative humidity increase, plants actually oftentimes become more susceptible to insects and diseases. It tends to be a more favorable environment for these things to grow and develop. Think of a tropical region. Right, I'm out here in West Texas. It's hot and dry, we see insects, we see plant diseases, but it's fairly minimal. The climate as it is being dry, being hot, being windy suppresses some of those populations, more on the disease side, particularly with fungus and bacteria, than on the insect side. But it is is. You do see suppression in hot, dry climates, especially with very cold winters like we have, as relative humidity increases and you get more tropical. This is a more temperate environment for not just our plants but for our insects, for our pathogens, for the bacteria and fungi that infect our plants. So a lot of times we actually see an increase in disease prevalence. Wet environments are conducive to bacterial growth, fungal growth, and a lot of times these pathogens are getting into the leaf through a wet leaf surface. So if it's real humid, it rains, that water sticks on the leaf. A lot of times it's really easy for that fungus to get inside or that bacteria to get inside.
Speaker 1:However, I was reading about this and there's some really interesting studies that sort of throw some wrenches in this general convention. Now I'm going to say up front that the short answer for almost any biological, botanical, zoological, whatever it is it depends. There are so many caveats in so much gray area. There is a wide spectrum in biology for almost anything that we're talking about, so it's hard to say definitively that yes or no, this is or isn't Okay. So the best we can do is teach through example. So it's going to vary. It's complicated, but one study I read it was in tomatoes and a fungus called Botrytis cinerea. Okay, this is a gray mold. So you'll see this a lot on your tomato leaves and it looks like just a gray mold. You also see Botrytis really commonly. If you leave a strawberry in the fridge too long, botrytis starts to grow and you get that moldy stuff on your strawberries.
Speaker 1:Botrytis is ubiquitous. It's everywhere in the environment. As you and I sit here, whenever you're listening to this, there's Botrytis all around you. It's not going to hurt you, but it's there, right. But it can ruin plants. It can cause photosynthetic capacity loss. It can ruin our fruits and our veggies and so it is problematic.
Speaker 1:So the study looked at tomatoes and the presence of botrytis in tomato plants at different temperatures and relative humidities, and what they found is that at low temperatures the conditions weren't right in general for Botrytis, which is a fungus, to grow good mycelium and all of that and infect the plant. So at low temperature it's not too bad. But as you increase humidity, even in low temperatures, the prevalence of this fungus does go up. So when we see higher temperatures at relatively low relative humidities, we see moderate response and so we would think as relative humidity and temperature increase, we should see an increase in the prevalence of this bacteria or this fungus, this disease, and we do. But we also see reduced infection in the plant. So while the fungus can grow more effectively in warmer, more humid environments I'm talking relative humidity of 80% and up it doesn't affect the plant as readily.
Speaker 1:And some of the speculation in the articles that I read which, by the way, I'm going to be linking these articles and giving you the references that I've used in the show notes in case you'd like to look some of these studies up. Really interesting stuff. They postulate that as temperature and relative humidity increase think the environment in a greenhouse the plant fitness overall increases as well. So what that means is, even though there's more of the pathogen present, the plant's healthier and those plant defense compounds can actually do a much better job of fighting off infection from our different things Maybe not insects as much, but definitely fungal pathogens, and there's a lot to this. Right. As a plant gets healthier, gets more fit, it can carry out its biological functions better. It can produce these toxins that help produce it from diseases. It can increase volatile organic compounds. It can do a lot of things to help make it healthier. Diseases it can increase volatile organic compounds. You can do a lot of things to help make it healthier.
Speaker 1:What we're really trying to do and one of the big, I think, high-level ideas behind integrated pest management is make your plant as healthy as possible. Give your plant the best environment that favors its growth in its own defense and maybe disincentivizes the infection of a pathogen, even if it's present. So the answer is yeah, maybe, as relative humidity goes up, even though a lot of our diseases, a lot of our insects, are happier at that level too, some of our plants may be happier as well. Now, this is not necessarily going to relate to houseplants. I think there's again a big spectrum here, but there are some interesting results that came with it. I would say in a greenhouse environment, yes, you'll get increased pathogen.
Speaker 1:I don't know availability, ubiquity, whatever, but as long as we're keeping our plants healthy, they are more able to tolerate some of these things in the environment. Essentially, we're just building up their defenses. They don't have an immune system exactly like you and I do, but it's not a bad analog. It's not a bad way to think it. The healthier we are as a whole system, we are, to some extent, more able to fight off disease and have better health overall. Now, that being said, even a very quote unquote healthy person can get sick, right? There are pathogens that will easily overcome our best defenses, which is why we have doctors and medicine and all of these things, and so the same is true for your plants. You have the best darn healthiest tomato plant in the world, but when the tomato hornworms show up, they're going to eat it anyway, which is why the plant has different strategies, like releasing volatile organic compounds to cull everything from wasps to birds to come eat the caterpillars. There's all kinds of defenses. So the short answer here is maybe it's better at high relative humidity, but it depends. And the long answer is that this is a complex series of interactions between a plant and its environment, whether that is antagonists in the environment, insects or harmful insects quote unquote harmful insects and diseases and things like that or just with the environment in general. So that's a good question and there's a lot of research on this. So I would encourage you, if that's something you're interested in, to check out the linked articles here. They're pretty fascinating and just look into it a little bit more because it is very cool.
Speaker 1:The next question that comes up is from tcarpenter605, also on threads. These are all going to come from threads today. Actually, the question is why isn't rooftop commercial gardening more popular? I think that's a great question and there's a lot to this. We don't probably have time to get into all the nuance here, but one of the short answers to why aren't we rooftop gardening more because I actually get to ask this question a lot, especially in big cities why are we not taking all of this roof space and putting gardens on it? Okay, there are a couple of reasons. One I think rooftop gardens are a great idea. Personally, I think anything we can do to break up urban heat islands. I think that any ways that we can make our urban real estate more green, whether that's at the ground level or up on top of a building, we should do that. Okay.
Speaker 1:Problems arise with the fact that a lot of buildings are not built from an infrastructure standpoint, a structural standpoint, to support a rooftop garden, because you know what Plants are heavy and soil is heavy and what's really heavy is wet soil. So you take your building and you're like you know what this building has 10,000 square foot of roof space. We're going to put a big rooftop garden here, cool. The structural loads of that building are intended to hold up natural, normal sort of things that it interacts with Animals, big rainstorms, snow, whatever to a certain tolerance and a certain certain capacity. But then you take a whole bunch of wood and you build raised beds. You fill those raised beds with soil or potting media, you put plants in there and you grow plants and those plants do the photosynthesis thing and turn all this carbon dioxide in the air into more plant. And so you're constantly increasing your weight load on the roofs of these buildings that are not designed for it right.
Speaker 1:And then it rains. Oh my goodness, it rains. We have a big rainstorm and soil, if you didn't know, is really good at holding on to water. It can absorb many times its weight in water. So you get these beds that are already heavy, full of heavy plants, full of heavy things, and then you put gallons and gallons of water on top of it. By the way, a gallon of water weighs about eight pounds, just as a metric to hang on to. So, one, your roof has to be able to hold this up and, two, that water has to go somewhere.
Speaker 1:Our buildings are a lot of times designed to shed water quickly. They don't want it necessarily standing on the roofs, they want it moving and going away quickly to shed over the sides of the building, down drain, whatever, however it is. But then we build all these structures that hold water in place and water is going to find path of least resistance to the ground. And when there's no resistance and it can just easily move across a roof surface and over the side, okay, cool, when you hold it in place, maybe the path of least resistance is through your office it can weaken the structure of a roof, which is, by the way, not great if you work in that building. So I believe that we very well could replace a lot of our roof line, a lot of our urban roof space, with gardens, and I actually think we should both commercially, socially. It's a great place to eat lunch, it's a great place to do a lot of things, but we need to be designing our buildings with green infrastructure and we need to be designing our buildings as we build new ones to support the weight, to support all of the different sort of flow rates and things that go with plants growing up there. So is it a good idea? Yes, absolutely. I think so. I think it requires a lot more effort to retrofit an existing structure to support that Not that it's impossible, it's done fairly regularly. Then it probably is to build a new building already with it set up that way. It's a good question. I'm actually a big component of rooftop gardening and urban green space, so I think that is something that, moving into the future, we should think more about.
Speaker 1:But I'm going to take a quick break, run some mid-roll stuff at you and then my last questions for today are all about houseplants. So we'll tackle those together. So stick around and we'll be right back. Hey there, welcome to the mid-roll Fancy. Seeing you here. How's your mom? How are your kids? How's the dog? Tell your dog I said hi, and also give your house plants a nice pat on the head for me.
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Speaker 1:Like I mentioned, some really good interviews, but if there's something specific you would like to hear, please let me know. And that's all I've got for you. So let's get into the second half of the episode and do some more questions. All right, we are back. I hope. I think I pushed the right button, we'll find out.
Speaker 1:So some other questions, and these are all houseplant related. So the first one is from my friend, ben Randall, who goes by Chef Ben Randall. He has a great podcast, by the way as well, which I'll link in the show notes. But Ben says okay, I've heard varying reports about whether indoor plants actually improve air quality. If they can do, which ones do you recommend for optimal air deliciousness in the home? Air delicious I actually like that quite a bit. Make your air more delicious. Okay, so some things about this.
Speaker 1:A lot of the conversation around this goes back to an old study by NASA, I think, like in the 80s, surrounding which kinds of plants will clean the air. They're looking at bioremediation for space travel, other ways that they can use plants as air filtration, things like that. Because if we're going to coexist on another planet certain people say that we are we're going to have to have plants and we got to figure out how those plants grow in space and how they're going to maintain a healthy ecosystem like they do here on Earth, because they're from Earth and the things that they do are based on evolution and development here on Earth, not on Mars or in a spaceship. So NASA has been working in astrobiology and astrobotany for a long time trying to figure out how this works and how to get its work, and it goes back and forth. Okay, so there are a bunch of plants out there that do potentially make air quality a little bit better.
Speaker 1:So this measurement is called indoor air quality IAQ and it's become a bigger concern in our homes as we've gotten better at building homes and that sounds weird, but you've probably heard of like sick building syndrome. So in the past buildings weren't really airtight, right. They leaked pretty readily. There was air exchange with inside and outside. So when you've got mold development, when you got different things, you would have some air turnover and the airflow in and out of the home Windows were open more. But in more recent history, if for energy efficiency, for making sure that we can heat and cool effectively, we've really sealed up our houses, and if you close all the doors and windows and button everything up, you're just recycling air inside the home. Button everything up, you're just recycling air inside the home and it's only when we open a window or open a door that we get any kind of air exchange, but it's not nearly as much as we've seen in the past. So we've seen things like mold increasing Again.
Speaker 1:They call it sick building syndrome. There's a lot of stuff that goes along with it Old buildings that have been sealed up for a long time. The air quality is really very poor. So the thought is, if I put plants in, will it fix it? So there's a few points here. Now again, there are a hundred different things we can study and talk about in terms of how do plants improve air quality? If they do, maybe they don't. One as maybe a high-level talking point.
Speaker 1:From a human health standpoint, being around plants is good. From a human health standpoint, being around plants is good. There are a lot of data out there looking from everything from plants in the hospital, plants in your home. Looking at physical well-being, mental well-being, a lot of other things, emotional well-being. Being around plants has physiological benefits for you, and this is like long studied empirical data for things that we know. If we are not feeling good, sometimes going outside and getting some fresh air and walking around in the park helps. There's data to back that up. Right? This is real science. So having plants around good thing, do it? Put plants in your house, get some house plants, put flowers in there. Whatever you want to do, it is a net benefit for your health, whether or not it affects indoor air quality. But reading some different studies and I read two or three different papers on this a couple of them were review papers looking at a wide sort of swath of data, there are some benefits and there are some things that probably don't work as well as we think.
Speaker 1:So one of the things that people talk about quite a bit is that having plants in the house will reduce carbon dioxide in the home, just as a crash course in photosynthesis. Plants harvest energy from the sun as photons and then they pull carbon dioxide out of the air and they go through this complex cascade of processes to essentially turn radiative energy, solar heat energy into stored chemical energy in the form of glucose and other carbohydrates. That is photosynthesis. We're taking carbon out of the air, using energy from the sun, converting that energy by way of carbon dioxide make sugars and different things. We're essentially taking heat, radiation energy, and turning it into chemical potential energy. Okay, that's the nutshell of photosynthesis. Unfortunately for my students, in about a week after as I record this, they're going to have to learn about photosynthesis in much less of a nutshell. So if you're one of my students listening to this, buckle up, it'll be fine.
Speaker 1:The other side of that is, as they are going through this process of photosynthesis, they're releasing oxygen into the atmosphere. Now, on a global sort of balance, it does lead to a net sort of increase in oxygen, but generally it stays pretty standard. Right? The amount of carbon dioxide in the air, if we are not pumping additional carbon dioxide into the air, would stay pretty stable because all the plants on the planet, from a molar gas exchange standpoint, do it at a rate that's pretty standard and pretty normal. Then we take fossil fuels and we burn them and we add extra carbon dioxide and the plants can't keep up. So they're producing oxygen, they're sequestering carbon dioxide, but we're still getting a net increase in the atmosphere.
Speaker 1:If you're inside your house and you're breathing, you're taking in oxygen and other things and using the oxygen and breathing out carbon dioxide. That is respiration, which is the biological inverse of photosynthesis. In a lot of ways, plants are also respiring. Every plant cell in general respires too. So they are also consuming oxygen and releasing carbon dioxide. It's just that photosynthesis, in the right conditions, in high light amounts, happens at a higher rate than respiration. So a plant, as it's actively photosynthesizing, outstrips the respiration rate right. So it's producing more oxygen than it is carbon dioxide, even though it's always producing both. Then we take that plant, we put it in our house in very low light levels and our photosynthesis rate drops. Okay, so we're still photosynthesizing, we're still respiring, but they're probably doing at more of an even rate.
Speaker 1:Generally speaking, if we want a growth and development way to look at this, if your plant isn't growing much, your photosynthesis and respiration are fairly equal because the resources that it's pulling in through photosynthesis are being burned at the same rate by respiration and the plant doesn't grow. If your plant starts to grow, then your photosynthetic rate is usually higher than respiration. This is an oversimplification, but it's not a bad way to look at it. So if you have houseplants that aren't doing much, it's probably zeroing out. If you have houseplants that are actively growing, you may be getting a little more oxygen than carbon dioxide produced. But generally speaking, in low light environments this is going to be fairly close for a lot of plants, even our tropical and low light plants.
Speaker 1:So from a CO2 standpoint probably doesn't affect the CO2 very much, what I think a lot of people think about is pollutants. So, whether these are microbial or particulates like dust and things like that, or organic compounds, gases, volatile organic compounds, things like formaldehyde and benzenes and different things like that, could the plant scrub those out? And the answer is yeah, to a certain extent. Yeah, one of these studies. I'm just going to read you a quote out of the study. The primary effects of the potential indoor plants on air quality were reduced pollutant levels, particularly formaldehyde, benzene, toluene removal, followed by increase in humidity and decrease in temperature. In addition, including various plant species could improve the effects of indoor vegetation on emulating air quality and microclimate conditions.
Speaker 1:So a couple of things are happening here. As the plants grow, yeah, we do see a potential reduction in some of these volatile organic compounds in the air. The mechanisms for how this happens are complicated and maybe not very well understood. The same is true for dust and other particulates. But it's true that the plants are diffusing some of these compounds into themselves through the stomata. They're pulling it in as they pull in CO2 and other air, and it gets metabolized a lot of times and stored in the plant as different things. That's a good thing. What we think may be happening too, and at a higher rate, is actually in the soil that the plant is potted in, because it turns out that fungi what we call, which means root fungus or soil area fungus is really good a lot of times at pulling some of these particulates out of the air so it could be diffusion through the soil and captured by micro. It could be captured by the leaves.
Speaker 1:They found that one plant may not be better than another, but differences in density on the bottom of the leaves, leaf size, leaf shape, different things. If you have a whole bunch of them and different kinds, it's probably better than just having, like, just a fiddle leaf, fig or whatever house. So we see some difference in some of these things and actually some improvements in indoor air quality. One study I looked at which was really interesting was looking at what if we took an active role in this and instead of just saying these plants are going to passively filter the air, what if we let them actively filter the air? And they looked at taking fans or different types of air movement devices and actually forcing air through the soil, through the plant canopy, through different things, and this probably showed some of the bigger reductions in volatile organic compounds and different things in the air. So maybe we just build biofilters in our house, I don't know.
Speaker 1:Can plants improve indoor air quality? Yes, but it's complicated and it doesn't do everything. Should you still have plants in your house? I vote absolutely yes. I vote yes. They are good for you.
Speaker 1:Whether they pull formaldehyde out of the air, they're a good thing, okay, sort of tagging onto that, my friend Farm Traveler, who has a great podcast and YouTube series as well, said what are the best indoor plants for low light conditions? There's a bunch of them, but I'm going to say my probably top three are pothos, snake plant and zizi plant. These are plants. Prayer plant is up there.
Speaker 1:Sometimes a fitonia or nerve plant can do pretty well, but you want things that are going to generally have a dark green color, a waxy cuticle, that are going to take low light conditions. Now I will say every plant, any plant, any house plant wants light, whether that's indirect light from a window or whatever. Bright indirect light is going to be great for your house plants. You can use grow lights. You can use different things. They. Indirect light is going to be great for your houseplants. You can use grow lights. You can use different things. They need light. It's just that some of these are a little bit better suited to growing in somewhat lower light conditions. So what I would say is go, look in the shade area of your garden center, look inside the conservatory parts and try some different ones. But for my money it's hard to beat a snake plant, it's hard to beat pothos in low light conditions, and ZZ plant, prairie plant and nerve plant do pretty well as well.
Speaker 1:Tagging onto that, just Jess Vice asks why are fiddle leaf figs so fickle? Yeah, yeah, they are, they are. Fiddle leaf figs are probably like the most dramatic houseplant you could have. You look at them wrong and they drop half their leaves. You move them and goodness, they'll complain a lot and drop all of their leaves. They like being in one place, which makes some sense, right? Plants don't move really.
Speaker 1:And if you think of an understory plant that's growing under other things in a tropical environment, the environment doesn't change much. It's the light conditions are stable, the air conditions and temperature and rainfall and everything else. It's fairly stable. It really doesn't change much over time. And in a natural setting if there is this big change in light, in water, in temperature, there's probably a large disturbance. That's trees falling down, that's canopy changes, they're going to let more light in or more wind through or whatever. A protective response of a lot of plants is when there is a lot of stress, when the environment changes, they drop their leaves to reduce the amount of water that they have to move through the system, because the water is released to the environment through the leaves.
Speaker 1:Leaves can be expensive for the plant to maintain from a resource standpoint. While, yes, that's how they get their carbohydrates through photosynthesis, they can usually go a little while on stored reserves until maybe disruptions in the environment stop right. They get better. So you take your house, plant your fiddle leaf fig that's happy in a certain corner and you're like you know what. It looks goofy in this corner, it should be in that corner and you move it to that corner. The plant immediately goes, ah, danger and it thinks like a tree has fallen. They don't think things, but like it's a disruption in its environment. So you just have to give it time.
Speaker 1:Usually, most fiddle leaf figs, if you move them from one light environment to another, one temperature environment to another where they can't see the TV, I don't know they tend to drop a bunch of leaves. Generally those leaves come back. If that's the case, just keep them well watered. Try not to disturb the root, the area of the root zone, as much as possible. Keep them well watered. Keep them at a temperature that is consistent. Don't put them by a super cold window where they're going to get big blasts of different temperature air Probably. Don't put them by a door, necessarily. Put them somewhere where it's going to be very consistent and over time they will leaf back out. Usually it doesn't even take that long and they'll keep growing. But yes, fiddle leaf figs super dramatic. They're gonna make a mess anytime.
Speaker 1:The last question I want to answer and I don't have a good answer for it and I'm not even sure this is what she was asking, but I'm gonna answer the question I think she was asking. It's from Bonnie Brantley of the Oz9 podcast. Bonnie asks where do we go? What do we do? Y'all? I don't know.
Speaker 1:Things are weird right now from an environmental standpoint, from an academic standpoint, for a lot of things, and I think the question of what do we do now is probably on a lot of people's hearts and minds. It's on mine for sure. My wife and I have had a lot of conversations about this. The one thing I know we don't do is quit, and what I mean is quit our jobs, sure, but also quit building community, quit being good to each other, quit taking care of our planet in the ways that we can through the power that we have, quit asking for better from the people leading us right. I don't think we quit. I don't think we ever do, because it turns out that hope is powerful and that just moving forward is powerful.
Speaker 1:Bonnie, I don't know what we do, I don't know where we go, but forward, but on. And that's about the best I got. And if you're asking a completely different question, let me know and I'll try to answer that one. But that's how that read to me and that is actually what's been on my mind a lot recently. So where do we go? What do we do? I don't know what the next step is, but I know that we have to take it Right. We have to keep moving, and that's what I'm going to try to do, and I hope that's what you're trying to do, and I'm going to keep answering questions and talking to cool plant people and talking about how cool nature is in our environment is and how precious it is and how much we have to protect it. That's my job and I think, whatever you feel like your job is in this world and I don't just mean the thing that gives you a paycheck, but like your function, your purpose hold on tight to that. Do that. Okay, that's all I got.
Speaker 1:Thanks for listening, thanks for being part of Planthropology. Again, thanks to you, the listener most. First and foremost, thank you for believing in the show and believing what we do. Thanks for your comments and just for being cool, okay. Thanks to the Texas Tech Department of Plant and Soil Science for all the support. Thanks to the award-winning composer, nicholas Scout, for the theme music for the show. Planthropology is written, hosted, produced whatever else it is that people do for podcasts by me and it's supported by you. And just your time and your attention. I love you. I think you are the best. Keep being kind to one another, especially now. If you have not, to this time, been kind to the people around you, maybe give that a try. It's pretty cool. Be good, be safe and keep being really cool. Plant people and we'll talk in a couple of weeks. Thank you.
