Episode 197: tiny plants with Leslie Halleck

Tiny Plants Book Cover.jpeg

Transcript

Episode 197

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Jane: Compact and bijou are the key words this week, as On The Ledge delves into the world of tiny plants. I'm Jane Perrone, your host, and I'm joined this week by Leslie Halleck, to talk about her new book 'Tiny Plants', plus I answer a question about a colourful Tradescantia.

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Jane: Thank you to Alison, who became a Crazy Plant Person this week and supported me on Patreon and Cherie, who became a Superfan. Also, I must give a shout out to Inga17494 in the Netherlands, who left a lovely review for the show. I heard from Lynette who was listening back to an older, an old, old episode, actually I think it was episode 26, off the top of my head, about old houseplants. She shared the story of her night-blooming cereus aka Christ in the Manger, that's Hylocereus undatus, for any botanical Latin fans. It sounds amazing because the cutting that her dad had was from his grandmother. The dad was born in 1933, so you can imagine how old this plant is, and Lynette has passed on a cutting to her own daughter to keep the tradition going. Lynette says, "This plant is a part of our family history". How wonderful to still have it with you. These plants can go on for decades. It's so lovely to know that it's continuing to bring you all great joy. Wouldn't you just love to be able to have the magical skill of being able to touch a plant and, a bit like Spock doing a mind meld, you could then access where it's been. I think if I was going to have a superpower, that might have to be it! A plant mind meld would be amazing, wouldn't it? But Lynette, thank you for sharing that with me, and if you've got any stories about old plants, I would still love to hear them.

Speaking of which, it's coming up to episode 200 of the show and this is a shout-out. I would like to know from you, for this episode, what has changed in the world of houseplants for you since February 2017? So, maybe you have gone from zero houseplants to 200 houseplants, maybe you have lost half of your collection because of an incident that happened during the pandemic, maybe you've got really into Hoyas or spend a fortune on Aroids? I'd love to know from you how the world of houseplants has changed for you since On The Ledge started in February 2017. So you can just drop me a line to tell me this, or you can record a voice memo and send that over. Either way, the address is ontheledgepodcast@gmail.com Do not be shy! I love to hear from you guys! Don't think, "Oh this is a shout-out for other people who listen to the show". No! This is a shout out for you, yes you, so please do respond! This episode will be really rubbish unless I get lots of responses, so please, please, please record a little memo. It can be up to two minutes' long, but 20 seconds is fine. What's changed for you in the world of houseplants since February 2017? I need to know!

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Jane: You may remember Leslie Halleck from previous episodes of On The Ledge. She has joined me to talk about growlights, for instance. Leslie is a Dallas, Texas-based horticulturist and the author of many books on plants. Her writing is always science-based and really well researched, that's one of the things I love about her, plus she's also a massive plant geek, so I was really excited to get her on the show to talk about her new book, 'Tiny Plants', and I started off by asking her how the book came about.

Leslie: Sure! I call it my "origin story" with my love affair with tiny plants. I did my undergraduate degree, my bachelor's degree, in biology and botany and I didn't have time to do an internship while I was going to college. So I wrapped up my degree and then took on an internship with the University of Puerto Rico, which was amazing because I got to go down to Puerto Rico and be embedded in the El Yunque National Forest up at this little tiny research station, way up in the mountains. We couldn't get up and down ourselves. We were sequestered there, me and a few other, various plant researchers. We were there to collect data and observe the effects of Hurricane Hugo, which had come through the rainforest in 1989 and completely defoliated the entire rainforest. Pretty amazing. So, of course, the University of Puerto Rico was looking at how does a rainforest regenerate from something like this? How does the natural environment come back and how is it different once it does? So I was there to work on that project. I was there for about four months, of course through hurricane season, which was interesting, but it was really one of the most wonderful times in my life because I'm sequestered in this beautiful rainforest, surrounded by nature, just trekking out in the jungle taking data every day, which I always tell everybody the happiest that I am is when you drop me off in some remote rainforest jungle forest somewhere and I can just trek around and look for plants! It's a wonderful experience! So one day, as I'm out in the rainforest and all of my rain gear with my waterproof notebooks and pencils taking data on the trees, we were specifically looking at tree regeneration, huge trees, of course, in the rainforest. So I'm focused on these 300 foot, huge tropical trees that took several of us reaching around with our arms to measure the DBH, the diameter of the trees. I glanced over to a portion of the plot I was working in and I just happened to see this little tiny speck of colour, which is unusual because when you're on the forest floor in a rainforest, you're not necessarily surrounded by tons of flowers and colour, you're surrounded by trees and vines and a lot of greenery and a lot of decomposing leaves, but every once in a while you spot a flower, but this was so tiny. So I headed towards this group of boulders and discovered, to my utter glee, a population of really tiny micro orchids, Lepanthes rupestres, and the flowers are only about a millimetre or so, the leaves are about an inch, two-and-a-half centimetres and I just was utterly fascinated. I, of course, abandon the work that I'm supposed to be doing and spend a bunch of time trying to get film photos, which in the rainforest, if you've ever taken a film camera into a rainforest, it can be a little bit tricky to maintain your photo film integrity, but that was it for me. That was the beginning of my total obsession with tiny plants, all things tiny, really. Finding those micro-orchids in the rainforest - in fact, that species only grows in that area, so it was a really unique find - that was it for me! So, after that, I started collecting tiny plants. I started building vivariums for Poison Dart Frogs and other herbs and, of course, that's a situation, when you're building an environment like that ,you really have to get the plant species right. So, take a dive into vivarium-building, inevitably you're going to find yourself surrounded by a world of itty-bitty, tiny plants.

Jane: What a wonderful introduction to that you've given. You've really painted a picture there! Can you explain what are some of the evolutionary explanations for why some plants just stay really, really small and get advantages from doing that?

Leslie: The predominance of very tiny, and we're talking genetically tiny plant species here, are a bit of a paradox. Sok, if we talk about our traditional understanding of botany and plant physiology, one would assume bigger is better. As long as there's enough water availability and sunlight availability, plants evolve to be bigger, with bigger leaves, so they can collect more sunlight and grow bigger and dominate their environment, so that they can take up as many resources as possible. It comes down to competition. So it would seem logical that, as plant species evolved, that we would end up with mostly large, not just large, but large-leafed plant species. However, the paradox is that research is showing that very, very tiny plant species not only compete, in terms of number of species in the same environments, with large plant species, but often outnumber them. So you think,"Okay, if bigger's better, if bigger leaves can collect more sunlight and take up more resources in a space, then what's the evolutionary advantage of a plant species staying very tiny?" and when I'm talking tiny, we're talking under a few centimetres, very, very tiny species of plants. So there's a few different theories, and some are very obvious and some aren't, as to the benefits, the advantages of being tiny. So why do tiny plant species still persist in the same growing environment, under the same environmental conditions, that very huge tropical plants or conifers exist and a very simple obvious reason is simply that tiny plants can fill up, they can multiply within the same amount of much smaller space, so they can pack more individuals, if you will, into a much smaller footprint, which means they can reproduce more economically. Their tiny, tiny seeds can be produced much faster than larger-seeded species, so they sort of have a competitive advantage in terms of space and speed. So reproductive economy is what we call that. So that's one more obvious thought process or theory as to why tiny plant species still persist from an evolutionary standpoint and maybe even are increasing in numbers relative to larger-leafed plant species. But then there's also a really interesting relationship which comes into play when you're thinking about how you care for your tropical houseplants and that is the relationship between humidity, water at the soil, root level, air temperature and not only just air temperature but cold temperatures at night. So something that many houseplant keepers might not think about is that tropical plants can actually overheat in the hot climates where they're endemic. You think, "Well, these plant species grow in very hot climates, so that must be what they like" but they're able to thrive in those climates through really active transpiration. They're cooling themselves through transpiration and, of course, you need lots of water to effectively transpire enough to cool very large leaves. But what big leaves with big barriers of air around them are not good at doing, is actually pulling heat out of the air. So, as temperatures get more extreme, colder, so, say you move away from the equator and night temperatures get very cold and maybe there's less water, a tiny-leafed plant has an evolutionary advantage in that it's able to stay warm, if you will. It can pull more heat from the air around the leaf. So it can survive in temperatures that are colder than a large leafed tropical plant can. So there's all of these really interesting dynamics around, not only just being efficient in terms of reproducing or using resources in a smaller amount of space, but tiny, tiny leafed plants are better at keeping themselves warm and potentially keeping themselves cool. So that's why you usually see tinier leafed plants as you get further away from the equator and temperatures get colder at higher elevations. So it's a really interesting phenomenon to look at the morphology of plants as the natural environment changes and to understand that it's not all about access to water and sunlight, it's also about the interaction with temperature and temperature extremes. So it's really fascinating, if you're into botany and you're into learning about how plants evolve. It's an interesting, emerging topic you can dive into.

Jane: Well, that is really interesting and some of that I had never thought of, so that's really useful to get that insight, Leslie. I think one of the things that's confusing, when people first get into houseplants, is they go into a houseplant shop or a garden centre and they think they're buying a tiny plant for their terrarium. They're not buying a tiny plant, they're buying a seedling, a young plant that's going to get much, much bigger, and this is one of the things that I think people get confused by. They do a lovely job planting up a terrarium, but they've picked completely the wrong species because they're not actually tiny plants and this is where your book comes in, in terms of giving that information about what plants will actually stay small, but I'm guessing there's no real way - other than knowing what species you've got - just from looking at them in the shop, whether they're a tiny plant or a young plant that's going to get big. Is that a stupid question? Do you know what I mean? I don't know how to explain that any better!

Leslie: I actually address this in the book. There is the difference between naturally, genetically tiny plant species and artificially-managed size, when it comes to plants, or just age of a plant. Most of the plant species that you are getting at a traditional garden shop, or online, in terms of standard houseplants, you can buy a two inch/five centimetres or so pot of something that's only the height of your finger and you think, "Oh, this is going to be perfect for a terrarium! It's so small!" but, like you said, what you're really getting is a very young, rooted tip cutting, or a seedling, potentially, that simply hasn't grown to its mature size yet. Once you put it into that terrarium, give it a year or so, and all of a sudden it doesn't fit in that terrarium anymore. Then there's also other artificial means to hormonally, chemically keep plants small and you'll find this in the commercial growing industry for many ornamentals, for garden annuals, for example, where growth inhibitors are applied to plants to keep them small and compact and once they grow out of that chemical application all of a sudden, they're a much bigger plant than what you thought you were going to get. So my book, 'Tiny Plants', focuses on species that are genetically tiny and remain tiny at maturity and that's the trick. So if you're actually trying to have a planted terrarium, a standard-sized planted terrarium, you're really going to have to be thoughtful about the species, and that's what it takes. You have to get to know the species that you're buying because just looking at something in a garden shop, just because it's in a small pot, does not mean it's a tiny plant species, does not mean it's going to be able to be sustained in a standard-sized terrarium indefinitely. So you're absolutely right but that's an epiphany for people and that's a connection they may not make until maybe they see a book like mine and go, "Oh, there is a big difference between young plants and genetically tiny plant species!". Absolutely!

Jane: You talked a bit about terrariums there. Tiny plants are great in terrariums. Why is a terrarium a great environment for a tiny plant and can you give us some examples of things that do go well in a terrarium?

Leslie: Well, I want to give full disclosure that 'Tiny Plants' is not a terrarium-building book, so I want to be clear about that because there are so many great terrarium-building books out on the market already, but what I do, is introduce you to tiny, high-humidity plant species that you can plant directly into a terrarium, or simply grow as potted specimens under any type of glass, be it a Wardian case, be it a cloche, be it an upturned glass canning jar. You name it! Growing under glass, be it a planted terrarium or simply a specimen placed under glass, can actually be a very low maintenance way to keep a pretty sizeable collection of cool species of plants that might be more challenging for you out on the windowsill, in terms of regular watering. So it's a little bit counterintuitive. Planted terrariums can be a little bit more complicated in terms of making sure that you build the drainage layer properly and you're managing water inputs, but if you're growing tiny potted specimens with glass cover, or set inside a glass terrarium or in a Wardian case, which is my favourite way to do things, it makes caring for those plants incredibly easy. So if you are really wanting to enjoy collecting higher humidity species, ferns - micro-orchids, micro-peperomias, little Sinningias, little tiny Gesneriads that really can't make it out on the windowsill without a lot higher humidity - then growing under glass is the way to go. But you really have to use plant species that stay tiny if you hope to maintain that collection, or that display, or however you've planted your terrarium. You have to use tiny plant species or they're going to outgrow their space. So I love growing tiny plants under glass because, while some of these species might be perceived as some of the more challenging ones to take care of, once you put them under glass they become some of my easiest plants to take care of, so it's really an interesting phenomenon.

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Jane: More tiny plants with Leslie Halleck shortly, but now it's time for Question of the Week, which comes from the aforementioned Cherie, who became a Superfan this week and wanted to ask a question. So why not Cherie!? Let's hear your question! It relates to a Tradescantia Quadricolorbought from a nursery, but now people are telling Cherie that it's a Tricolor and Cherie is asking is this just a sales gimmick? If you want to have a look at the plant that Cherie bought as a Quadricolor, please do take a look at the show notes where you'll find it under the Q&A section and if you take the briefest of web searches, you will find that Tradescantia Quadricolor. What is it? You'll be a bit confused because there seem to be two different plants being sold under this cultivar name. The one that Cherie seems to have is called Tradescantia fluminensis Quadricolor and it's got green and white striped leaves with what I describe as a pink flush to some of the leaves. Let's just count green, white, pink. I think that equals three colours. I'm not sure where the fourth colour comes in. Sometimes you will see that the pink eases into purple, so perhaps that's why it's being called Quadricolor? As far as I can find from my research -- and let's be clear, the Commelinaceae family that Tradescantia is part of is a bit of a mess, taxonomically. I say this about every single family of plants that I name! It's a confusing business, this business of naming plants! - but, anyway, the Spiderworts Commelinaceae, they are in a bit of a mess. I think that the horticultural trade makes things worse because they tend to sell things under names that have been given to the plant without due process of taxonomic research, so you get yourself into this problem where two different plants are being sold as Quadricolor.

Presumably, they're selling this Quadricolor, that is under the Tradescantia fluminensis species, as a separate thing from what I've always thought of as Quadricolor and which is the one that you'll find in the books such as it is, is Tradescantia zebrinaQuadricolor. This is the one that I would recognise and call Quadricolor and, if you see pictures of that plant, you will see clearly that it has four colours. If you get a nice specimen of this you will see that it comes in creamy white, green, purple and pink colouring and it really is quite different from the plant that's being sold as Fluminensis Quadricolor.

I found a couple of good sources of information on this particular dilemma. There's a website called Commelinaceae-plants.blogspot.com - I will link to that in the show notes - which has a lot of information about cultivars that are being sold under incorrect names and so on and so forth. What that website does tell me, is that Quadricolor refers to zebrina, not fluminensis. Any Tradescantia nomenclature experts, please do get in touch and help me out with this, but that's what I have grasped so far.

There's also a good guide to Tradescantia cultivars on the premiersucculents.com site. Again, I will link to that in the show notes, but I think what I would say, Cherie, is that, yes, as far as I know, the plant that you've got looks like it has been labeled - taxonomically, anyway - incorrectly. We've seen it before. I've mentioned on the show that there's a certain plant called Streptocarpus Pretty Turtle, being sold by many outlets here in the UK, which has come from a Dutch nursery and it's not a Streptocarpus, it is a Primulina. This does happen and I think this may be what's happened in this case. This Quadricolor cultivar name has been attached to a plant from a different species just because it's quite colourful, whereas actually, it's not quite the plant that should be called by that name. Isn't this confusing? I wish this didn't happen. But I would say that you've got a beautiful plant, Cherie, enjoy it, love it, a lot of money and time is spent buying Quadricolor, the one that I would call Quadricolor, the ZebrinaQuadricolor. They are quite expensive and, yes, they are glorious, but I would say that all Tradescantias can look absolutely amazing. They're an easy plant to look after but they're a difficult plant to make look really good: you have got to put some work into it, in terms of keeping it well fed and watered, pruning and keeping it from getting too lanky.

Just to confuse matters further, the picture on the RHS website that supposedly shows Tradescantia zebrina Quadricolor looks very much, to me, like a regular Tradescantia zebrina, so nobody seems to be able to get this right at the moment! I guess it's not that surprising, a genus that's just so popular and has been bred and bred and bred. A lot of this stuff happens, which is a great way of marketing plants but it's not necessarily that easy for those who want to be botanically accurate with their names.

There's added difficulty because Tradescantias can really change their colours according to how much light they're getting, like so many plants. They can take on a pinky purpley blush when they're exposed to more light, they can get paler, they can get darker, all down to light exposure. So getting to grips with what is what is tricky! If you've got a question for On The Ledge drop me a line ontheledgepodcast@gmail.com and do include all the details you can. A picture is fantastic, as is info about where you're located and how long you've had the plant and that kind of thing really helps me to answer your question accurately. Right, now back to Leslie for more tiny plant chat.

Jane: Let's talk watering.

Leslie: So in the book, obviously, I provide quite a bit of general maintenance and care information , I broke the plant profiles into two sections, which you'll notice. One of them is for the windowsill, plants for the windowsill, so open air culture, as I like to call it, and those for under glass. Essentially, these are broken up into these two categories by their water and humidity needs, if you think about it. So, tiny plants for the windowsill are going to be plant species that thrive in lower humidity and don't need as regular a watering schedule as plants with higher humidity needs. So you'll find that, of the species that I have shown you for on the windowsill, even though they're tiny, they're actually relatively easy to maintain in terms of your watering schedule. Overall, tiny plants require much less resources, less water. Now, some plants for the windowsill, container size is important. Obviously, for all these plants, you have to look at the root system of the plant. Obviously, tiny plants are relatively going to have much smaller root systems, so you're going to need to be mindful about the size of pot that you use, maybe even more so for tiny plants than with standard size houseplants because it's very easy to rot a very tiny plant with a very small root system, by planting it into something which you might perceive as small, like a four or five inch diameter container, that might seem small to you but for a plant species that might have a root system that's less than a couple of centimetres deep that you can rot plants. So the trick that I start out with first, when it comes to watering, is be mindful of the type of container. Do a little bit of research into the root system of that plant so that you know how small or how big you can go. Here's one example. Have you ever grown Lithops, living stones?

Jane: Yes.

Leslie: They can really vex a lot of people because they're very sensitive to water and they have a dormancy period. What's interesting about Lithops is that they have a relatively large taproot and long taproot. So do Pygmy Sundews, which are one of the tiniest plants I profile in the book, but they have a very long root system. So you might actually use a taller, deeper container for one of those very, very tiny plants because its root system dictates it. That's going to help you better manage that water. Now, tiny plants for the windowsill may require more frequent watering because they're in a tiny pot. It's going to dry out a lot faster than your standard houseplants. If you are a habitual over-waterer, this is great for you because you can water more frequently and those plants are just going to dry out more frequently. So if you've got the species in a size appropriate container, chances are you aren't going to over-water it. So that's the benefit of some of the tiny plants there. Now, you go under glass and, of course, that changes a lot, but I find that certain species of tiny plants tend to be a little bit more sensitive to water quality and I talk about that in the book, and also fertilizer. It's very easy to burn your tiny plants much more easily, so you want to look at maybe diluting your fertiliser even more and I talk about that in the book. Little tiny squirt bottles, that's pretty much how I water most of my tiny plants. Don't try to water a tiny container with a standard watering can. You'll make a mess! So I love little squirt bottles so you can pinpoint water. Then there's a couple of more unusual watering methods I mentioned. One of them is swamp watering, which might be randomly new for a lot of people. Swamp watering is, I kind of equate that to dangling your toes in the water but not submerging your feet or your legs all the way. So, for example, some micro-orchids, or, say you've got a Kokedama Fern or something that really is an epiphytic plant that really needs higher humidity or more regular water access to the root system but submerging that root system under potting media or in Leca with water all the time will rot it. That's not going to work. So swamp watering is my in-between approach, where I will set the base of a mount that an orchid or a fern or something is on, or suspend using fish line, or something like that, the plant over a container that has water in it but just dipping the tips of the root system into that water, so that it's not submerging the root system. There's still a lot of air around the roots but a few of the root tips have continual access to water and I found this to be a really good strategy with certain orchids, or really any epiphyte that you want to mount onto something, or that you want to suspend into a vase or an open-air terrarium.

Jane: It's reminded me, actually, of something that's come onto the market here in the last couple of years, which is houseplants mounted on lava rock? They're sold in a tray. Me, being cheapskate, I'm like, "I could make that at home!". Like you can, obviously, buy it as a whole setup, which is lovely, and lots of people want to do that, but it's the same principle of that water being drawn up through the rock and the plant getting its water. But my mind starts whirring about ways that I could do that with my own construction.

Leslie: Yes, that's almost a version of swamp watering because that porous rock or other structure would basically sit in a little bit of water all the time. That's almost more like a wicking system but those root tips will grow down and touch the surface of the water, so you get the best of both worlds. You get a little bit of continuous water access to those aerial roots but you aren't submerging them, which will quickly rot many of them. It's a good hybrid watering strategy. I see a lot of folks growing epiphytes, basically, passively hydroponically, like in Leca, submerged in water all the time. I think that can be a little risky because, obviously, you are not aerating those roots the way that they would like to be. So swamp watering gets you the benefits of continuous moisture without submerging that root system.

Jane: And anything that allows you to put some water in there and then go away without panicking for a few days is a good thing. I think that's my take on it because I'm not an over-waterer, that's for sure. I'm very mean with the watering can!

Leslie: I am too.

Jane: I really love those systems. Any system like wick-watering, where you can just leave things and let the plant get on with it, is a plus as far as I'm concerned and has really allowed me to start growing some plants that I thought I was just never going to get anywhere with.

Leslie: You'll see, for example, the Pygmy Sundews, or some of the other tiny carnivorous plants I talk about, the ones that I feature don't need to be under glass in terms of humidity but they're bog plants. So you can just set those pots in an inch of standing rainwater, preferably, and you will note in my book, 'Tiny Plants', I do talk about the fact that I do use collected rainwater for most of my itty-bitty tiny plants and micro-orchids just because they respond better to rainwater and with carnivorous plants that's a pretty standard recommendation. Those can sit in open-air culture, but in an inch of water all the time, so it's that same kind of swamp watering situation; a perpetual bottom-watering, depending on their dormancy cycle. People will always say, "Oh gosh, how can you go on vacation with all these tiny, tiny plants? They're so sensitive!" and I say, "Well, actually, most of my tiny potted specimens that are really trickier are high-humidity and I just set them in glass jars, or I set a glass jar over top of them." I love to collect vintage glass vessels and you'll see a lot of those in the book and that little potted plant just sits inside that glass vessel and it can go weeks without you ever opening it or watering it. So it can actually be a lot less stressful when you leave and go away.

Jane: Where do you pick these things up? Is it junk shops or auctions or...?

Leslie: Yes, yes and yes, and online, but it's great because you're recycling materials which is nice. So if you are trying to be a little bit more sustainable in your plant collecting, a lot of my tiny plants grow in little handmade pottery. I'm a big fan of handmade artisan pottery, so I like to look for little handmade pots, but you can recycle all sorts of vessels for tiny plants because you can grow Sinningias in thimbles, literally, so you can recycle all sorts of things. Even vases, even just plain old glass vases that have piled up from floral deliveries you may have gotten in the past. The clear glass is best but, yes, I love going to vintage, like you say, junk shops or antique shops. You can find a lot of really cool glass vessels in places like that.

Jane: That sounds like a fun weekend activity just right there!

Leslie: I'm happy to indulge anyone's obsession or new obsession on that or if you're looking for an excuse to add to your vintage glass collection, you're recycling, you're being environmentally responsible!

Jane: Here in the UK we have something called the car boot sale. You go into a field somewhere, early on a weekend morning and people have got, like, trestle tables set up just outside their car. A car boot sale, I can tell you, is a really good place to go to get things like this because there's just all sorts there that you can pick up really cheaply. So I don't know if you have that in the US, but car boot sales are the other way to go?

Leslie: I love that! I wish we had car boot sales. We have crazy markets. They're usually more static. There's a location and you can go and antique fairs, things like that. I'm always looking for good glass domes that you can sit on top, so that's the sort of thing I'm always scouting for, and some of the larger domes. I've also been gifted some of the cutest, teeniest, tiniest little micro-vessels. I have some of the teeniest, tiniest little cloches and you'd think you could never sustain anything under that but I keep a lot of micro-Sinningia in incredibly tiny glass vessels and it's terribly satisfying.

Jane: I think Sinningia is long overdue a renaissance. In fact, there are so many Sinningias, I just had a look on the Gesneriad Society seed fund and the Sinningia section is enormous. There's hundreds of them! I was thinking, "Gosh, I don't know where to start!" but I can imagine that's a whole heap of fun. You've just got to find the ones that are the micro-cultivars, or species, as opposed to the larger ones?

Leslie: Yes, the Sinningia pusilla, that's your classic micro-species. There are a few others and then there are some natural varieties and a number of cultivars that are available. They can be difficult to find. One of the things that I will say to folks is that, occasionally, I'll get the comment, "Well, I wish you had covered more common species in this book" and my point is, well, then there wouldn't be a book because the whole point is that this book, 'Tiny Plants', introduces you to species that you don't really know about. That's the whole point of it! Tiny plant species like these are not at the forefront of the plant marketplace. You really have to dig around. You're going to find them with growers who grow for vivarium suppliers, for aquarium supplies. You have to go outside the normal plant shopping realm to find some of these and that was the whole point. I wanted to introduce people to a whole new realm of plant species they'd never heard of before, never seen before. What comes along with that is that you get to hunt a little bit more, which, personally, I find to be as much fun as growing the plants, searching and hunting for them. So you just have to be willing to do a little hunting. Many of the tiny Gesneriads, the little tiny Begonias, the little Sinningias, the little miniature African Violets, the micros, I love all those.

Jane: With that in mind can you just give us a few more species that are in the book, that are some of your absolute favourite tinies?

Leslie: Yes. You were talking about ferns, so you might give some of the little micro creeping ferns a try. My favourite for open windowsill culture... There's not a lot of ferns, especially tiny ones that you can just grow out on your windowsill, or a desk. Creeping Button Fern, Pyrrosia nummularifolia, is probably one of the easiest to grow. It's pubescent, it's got fuzzy leaves, it doesn't transpire as easily so it's able to hold more moisture and it's the cutest little thing. You can also grow it under glass and in a terrarium, but it's just as happy out on the windowsill, or on your desk, so that's a favourite. To go under glass, I love Climbing Snake Fern, Microgramma heterophylla. So that's a really cool one. I am obsessed with micro-orchids. There's a list in the book, but there are many genera you can get into. I would say Pleurothallis, as a genus, is probably the best place for a beginner to start with micro-orchids because they're fairly free-flowering and a bit more forgiving and easy to grow. They do need to go, most of them, under glass in an orchidarium, under a cloche, mounted in a terrarium, or something like that. Vietnamese Violets I don't think get quite enough love and if you struggle a little bit with African Violets, that's an option. Pygmy Sundews, I'm obsessed with Pygmy Sundews! They're about the size of your pinky fingernail, they're a little carnivorous plant but they're relatively very easy to grow and you can grow those out in open-air culture. They don't have to go under glass. I can go on and on with lists, but I mean there's a whole book. Here's the thing - and you know this because you're writing a book right now and you know this - I've written several books and you get a size limit, you get a word count and a picture count. There's a size that they've predetermined for the book and you've got to fit everything you want to fit in in that space. A lot of people think that, as an author, you write a book and you just write everything you want to write and you feature everything you want to feature and it's all going to go in the book. No ma'am! Unfortunately, you're limited to scope and size, so I could have easily included many more plants than are featured in the book but there wasn't space. So what I've at least done for you, on each plant feature, is I've also given a list of species that you can grow the same way. So I didn't have space to get photos and features in for all of the plants but, for each species, you'll see that I've got an extra list of a bunch more things you can look for.

Jane: It's a treasure hunt.

Leslie: It is!

Jane: You can be heading off and finding these things. I think that's a really fun element of it and, as you say, if they were available at every supermarket then we wouldn't be prizing them in the same way. Those tiny sundews sound so cool. Are they going to catch me some fungus gnats? Are they going to be useful if they're uncovered?

Leslie: Actually, all of my carnivorous plants that I keep indoors are handy with the fungus gnats. They definitely help out! So, in fact, I have pictures of my Butterworts that have fungus gnats trapped in them and I don't know if there's a picture of that in the book. There might be. But yes, they will catch fungus gnats, which is handy. There's all sorts of fascinating things that these little tiny plants will do. I tell you, there's nothing more exciting to me than when one of my micro-orchids actually flowers, or my little Sinningias are flowering. It's just so fun. If you are running out of space but you want to keep collecting, tiny plants are a great way to do that. If you don't have a lot of space to begin with but you want to truly be a collector, you want a few hundred species of plants in a very small footprint of space, that's what you get to do with tiny plant species. So once you've got your Snake Plant and your Heartleaf Philodendron and you've got these plants that actually get quite a bit bigger than most people realise when they buy that little pot at the garden centre, I wanted to give people a fun way to delve into a little bit more botany and be able to keep collecting, even if they were running out of space.

Jane: This is the point. Modern homes are just getting smaller and smaller, aren't they? Certainly, my house has very, very shallow window ledges, so having a small plant that can fit on a tiny space is a massive boon. I love my big Monsteras but, actually, they're a bit of a pain because they just get enormous so quickly, so I can see the benefits.

Leslie: Yes, I think a lot of people really aren't prepared for that and then, as new houseplant keepers, once it starts to get really huge and take over the space, they go, "Whoah! I didn't really know this was going to happen!" and, I will say, the handy thing - and there's pictures of this in the book as well - is that with all of the new growlighting technology that's out, most of the new growlights that are out and available are LEDs that are in that 20 to 40 watt range. I always have to break it to people that those growlights are really going to provide minimal supplemental lighting for many of your bigger medium to high light plants. They're not going to sustain them indoors. It's supplemental. That said, for teeny tiny plants which you can fit quite a lot of on a bookshelf, you can provide, really, all the light that they need with about 20 watts per couple of square feet, or a little bit less than a square metre. So, 20 to 40 watts, which is the ball park, if you really want to get into real light metrics you can go into my book, Gardening Under Lights, and I go into that there, but you get to use some of the really nice, prettier low profile little LED bars that you can under-mount in cabinets or bookshelves, which will keep groups of tiny plants very happy year-round. That's another benefit.

Jane: Yes, you could have a little shelving unit fitted out with your LEDs and have a whole mass of tiny plants under there that would all be incredibly happy.

Leslie: Which I do!

Jane: Who wouldn't love that? That sounds absolutely perfect, Leslie. Well, thank you for joining me today to talk about Tiny Plants. It's been inspirational, as ever at the end of an episode. I'm now thinking about all the tiny Sinningias and Sundews I need to go and get!

Leslie: I'm happy to encourage your habit! I won't apologise for that! Thank you for the kind words. This was a little bit of a passion project for me, so I was happy to be able to put at least a little bit of my love for tiny plants and, like you said, a little bit of science. I want to always respect my reader and give a little bit of science along with the art and that is horticulture; the art and science of growing plants.

Jane: Absolutely! Thanks so much, Leslie.

Leslie: Thank you.

[music]

Jane: Thanks so much to Leslie for joining me today and you can find out more about her book and see some images from 'Tiny Plants' in the show notes at janeperrone.com Whether your plants are teeny-tiny or several storeys high, I hope they bring you massive joy this week. See you next Friday. Bye!

[music]

Jane: The music you heard in this episode was Roll Jordan Roll, by The Joy Drops, The Road We Used To Travel When We Were Kids, by Komiku, and After the Flames, by Josh Woodward. All tracks are licensed under Creative Commons. Visit the show notes for details.

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I talk to horticulturist Leslie Halleck about her new book Tiny Plants, and answer a question about a colourful Tradescantia.

This week’s guest

Leslie Halleck is on Twitter and Instagram and her website is here. Her new book Tiny Plants is out now, published by Cool Springs Press. Leslie has been an OTL guest before… you may remember her from my episodes on plant propagation and growlights. Lepanthes rupestris was the Puerto Rican species of micro orchid Leslie found in her ‘origin story’ for the book.

Patreon Ledge Ends and Superfans can hear Leslie talking about micro orchids in An Extra Leaf 79.

Check out Leslie’s tiny plant tips and other info as you listen…

  • Take extra care when feeding tiny plants, as they are more prone to fertiliser burn.

  • If you struggle with watering tiny plants, Leslie recommends squirt bottles for watering tiny plants without making a mess.

  • Swamp watering is a way of watering that Leslie recommends for certain tiny plants including micro orchids and some ferns and other epiphytes where the base of a mount is placed over a container of rainwater, with just the roots of the root system submerged in the water.

  • Tiny plants that require high humidity can be placed in terrariums or under glass vessels such as cloches to cut down on maintenance.

  • Want to have a look at the Gesneriad Society seed fund list I mentioned? it’s here.

  • Sinningia pusilla is one of the Sinningias that fit the tiny plants category.

  • The species Leslie names as her favourites are the creeping button fern, Pyrrosia nummularifolia, for open windowsill culture: for under glass, Leslie suggests climbing snake fern Microgramma heterophylla

  • If you want to get into micro orchids, start with Pleurothallis species.

  • Leslie also recommends Vietnamese violets (Deinostigma tamiana) and pygmy sundews.

Scroll down for more images from Leslie’s book - click to enlarge the images. All images are copyright Leslie Halleck.

Cherie’s supposed ‘Quadricolor’.

Cherie’s supposed ‘Quadricolor’.

QUESTION OF THE WEEK

Cherie got in touch to ask a question about a Tradescantia that she bought as ‘Quadricolor’, but people have told her it’s actually a ‘Tricolor’. It’s pictured left, so have a look and see what you think! Lots of spiderworts are being sold as ‘Quadricolor’, but are they really what you think they are?

The world of Tradescantia taxonomy is, like so many other genera of houseplants that have been extensively bred, a bit of a mess.

Although lots of sellers are offering something called T. fluminensis ‘Quadricolor’, I can’t find anything that looks genuine telling me that such a name exists, and to me this plant looks very much like T. fluminensis ‘Tricolor’.

The ‘Quadricolor’ name is properly associated with T. zebrina: a plant with green, purple, pink and white striped leaves. (Unfortunately the RHS website, although it lists this plant, provides an accompanying picture that seems to show a straight T. zebrina rather than ‘Quadricolor’!) This plant tends to be pricey for a Trad, and harder to get hold of.

Have a look at commelinaceae-plants.blogspot.com for more useful info on taxonomy in the Commelinaceae family: premiersucculents.com also has a good guide.

Quadricolor update: Avery of Tradescantia Hub, a Trad expert, got in touch with these comments about Cherie’s question… you can listen to a full interview with Avery in episode 223 of On The Ledge.

The truth is, the current situation with cultivar names in the Commelinaceae family is even more of a mess than you described! For today's usage, your answer was right - Cherie's plant is the cultivar most often called 'Tricolor' (but also sometimes known as 'Quadricolor', 'Rainbow', 'Laekenensis', and various other names), and the cultivar most often called 'Quadricolor' is a variegated T. zebrina. But in fact there are several other issues with all of those names...

First is the species identity of Cherie's plant. It's usually labelled as T. fluminensis or T. albiflora (which is an outdated synonym for T. fluminensis) - but in fact it is a better match to the species T. mundula.

Second is the 'Tricolor' name itself. The oldest established name for this cultivar (from the 1800s) is in fact 'Laekenensis' named for it's place of origin, the Laeken area in Brussels, Belgium. Meanwhile, the name 'Tricolor' was widely used through the 1800s and early 1900s to describe a cultivar of T. zebrina with silver, green, and purple on the leaves (likely similar to today's 'Silver Plus' or 'Silver Sicilian', the most common zebrina cultivars in circulation).

And finally, there's the 'Quadricolor' name. This cultivar was first published in 1879 under the name Tradescantia Multicolor Mme Lequesne. Through the late 1800s and early 1900s it was widely sold as Tradescantia 'Multicolor'. But then in the mid-1900s, it started being distributed as 'Quadricolor'. And at the same time, another cultivar was given the name 'Multicolor' (a different variegated cultivar of T. zebrina, also known as T. 'Discolor Multicolor', and a third cultivar was given the name 'Mme Lequesne' (another T. zebrina with very thin and sometimes absent bands of silver).

In short: it's a nightmare! I'm in the process of researching the cultivation history of the genus, working on a complete cultivar list, and preparing nomenclatural standards for as many cultivars as possible - it will quite likely involve a lot of new or corrected names to resolve some of the issues. In the meantime, I'd agree with your use of the most common contemporary names of 'Tricolor' for Cherie's plant and 'Quadricolor' for the variegated T. zebrina. In cases where the species identity is in doubt, it's safest to give the name using the genus only (just Tradescantia 'Tricolor', rather than Tradescantia fluminensis 'Tricolor' or Tradescantia mundula 'Tricolor').

Want to ask me a question? Email ontheledgepodcast@gmail.com. The more information you can include, the better - pictures of your plant, details of your location and how long you have had the plant are always useful to help solve your issue!

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CREDITS

This week's show featured the tracks Roll Jordan Roll by the Joy Drops, The Road We Use To Travel When We Were Kids by Komiku and After The Flames by Josh Woodward.

Growing under glass, Flowering houseplantsJane PerroneTradescantia, sundews, carnivorous plants, GesneriadsComment