Tag Archives: Observations

Information, Even If You Don’t Want It: Integrated Pest Management

One of the issues with which we struggle at the Triffid Ranch is a bit of a logical leap in what carnivorous plants can do. Based on phone calls, emails, letters, and incessant queries at shows and events, the logic starts with the given “Carnivorous plants attract, capture, and digest insect and other animal prey” and veers Immediately into “carnivorous plants will take care of my bug problem.” This leads to calls and queries. “My house abuts a stream, and the stream attracts mosquitoes. I need a pitcher plant to eat all of the mosquitoes.”  “My kids leave the door open all day, and we need a Venus flytrap to eat all of the flies they let in.” “My roommate won’t take out the garbage, so I need a flytrap to eat the flies on the garbage.” Sometimes this goes to extremes: “I saw ants at the end of the driveway, and I want to build a berm around my house and cover it with flytraps to get the ants.” Or my personal favorite and a reason why I refuse to return to one show at which I displayed plants in 2013, “Cool! Got anything that will eat bedbugs?”

To all of these, I try to explain, over and over, that while you can get great satisfaction in watching a Cape sundew digest mosquitoes, and even add Battle Boy sound effects to liven things up, one plant or even a thousand won’t get rid of every insect in your time zone. It’s not even a matter of picking wildly inappropriate plants, such as the people who ask repeatedly about using Venus flytraps to control fleas. (The simple answer: they won’t. Even sticky-trap carnivores such as sundews and butterworts may catch fleas, but they won’t break the life cycle.)  Besides, as entomologist and brilliant bug blogger Gwen Pearson notes, you’ll never bug-proof. your house. We lost the war against bugs, spiders, and other exoskeletal creepies about 400 million years ago, and barring a mass extinction that wipes out every arthropod (up to and including the millions of skin mites that eat dead skin cells on your body), we stand no chance of changing that.

That said, while wiping out pests is a lost cause, it’s possible to keep their depredations down to a dull roar. That’s the basic idea behind the concept of integrated pest management, which attempts to minimize horticultural chemical use by understand that complete annihilation is impossible, but cutting populations down to a dull roar isn’t. 

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“You are Number Six.”


For example, one of the more pernicious pests in most households this time of the year is a recent invader, having only been documented in large numbers since 2004. Since then, the shelf elf has been found in living rooms and bedrooms across the United States and Canada, never appearing in the same place twice during the holiday season, and resisting all attempts at capture or restraint. Not only will they return each year, but they have a propensity for breeding out of control, and all efforts at spaying and neutering have been complete failures. They also have a distinctive hive mind, reporting back to a central dominant individual known as a sinterklaas, thereby making efforts to collapse the hive structure nearly impossible. Recent reports suggest that they’re able to communicate with the sinterklaas from considerable distances, but whether this is by telepathy, by Extra Low Frequency vibrations through earth and water, or by pheromones or other vaporous output is unknown. What IS known is that they seem to be especially astute at viewing and modifying the behavior of children, merely by watching and waiting, and the intimation of a reward in exchange for those behavioral changes. Also unknown is the reason for initiating the behavior changes, but research suggests a model comparable to that of the pathogen Toxoplasma.

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“It’s an ugly planet, an Elf planet, a planet hostile to life as we know it!”

Thankfully, there are ways to deal with this menace using IPM, so let’s fire up the appropriate soundtrack and get going,.

The first and most obvious control, chemical, is problematic for multiple reasons. In fact, that problematic nature is why integrated pest management was founded in the first place, because the overuse of pesticides was becoming a significant issue in both farmlands and in residential areas. As a last resort, chemical repellents and poisons have their place, but be warned that most of the effective options for invasive elves also have negative effects on the human population. Butyric acid in aromatherapy bottles works sporadically as a repellent, but the enterprising and cost-conscious homeowner should consider making a custom mix of 75 percent potassium nitrate, 15 percent sulfur, and 10 percent charcoal, or an equal weight of gasoline and polystyrene foam. When ignited, both have an effect on local elf populations: when mixed up in sufficiently large quantities, the effects may be seen from low Earth orbit.

The second control, mechanical, applies to most traps, grinders, zappers, or pitfalls. Repeated vivisections of shelf elves reveals no vital organs or internal structure particularly susceptible to anything other than overwhelming force, and documented sightings exist of shelf elves recovering and attacking immediately after crushing or flattening that would kill most Earthly life. With this in mind, further research continues with finding all-inclusive mechanical controls that can anticipate and neutralize shelf elves before the sinterklaas can give them new orders. The choice of mechanical control is up to the one applying it: from personal experience, while American, Chinese, and Australian controls are have their advantages, Russian controls are low-maintenance, exceeingly durable in multiple environments, and extremely effective.

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“Elbow rocket…NOW!”

This leaves the obvious and logical choice: biological controls. Since shelf elf study really only started a decade ago, many “facts” about their behavior, reproduction, natural history, and evolutionary history are little more than assumptions, and are forcefully disputed. One of the most disputed involves predators in their original environment before coming in contact with humans. Due to their lack of internal structure, which leads some palaeontologists to make comparisons to the extinct Ediacara faunas of the Vendian Era (Crusher, Franklin, & Shaw, 2010), nothing other than highly contentious fragments exist in the fossil record, and genome sequencing has been stymied by a complete lack of sequenceable DNA (Banner, 2011; Richards, 2012; Hoshi, 2012). One thing is certain, though: in multiple tests in captivity, a wide variety of predators actively attract, capture, consume, and digest shelf elves (Logan, West, & Furter, 2015). No widespread field tests on predator selection have been done to date, and the understandable concern is that any effective introduced predator may itself become an invasive species, as demonstrated with the introduction of the cane toad (Bufo marinus) in Australia (Benway, 1959; Duke, 1971).

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One very promising avenue of biological control involves the use of exoparasites, which utilize host organisms during stages of their life cycle. Again, the largest concern involves whether the exoparasite stays with one host or utilizes multiple host species. An equally vital concern, based on recent studies, is whether shelf elves will evolve changes in structure or behavior to bypass parasitism, causing the exoparasite to seek out new host species or become extinct. Using cicadas as a model, extreme predation or parasitism may cause shelf elves to spread out infestations over multiple years, in an attempt to keep parasites from depending upon them every holiday season. Alternately, shelf elf emergence may start earlier in the year: reports of shelf elves being spotted as early as July may be examples of this new behavior.

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“It has a funny habit of shedding its cells and replacing them with polarized silicon.”

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“I could lie to you about your chances, but you have my sympathies.”

Due to the challenge of the shelf elf life cycle, with large populations accumulating only in the month of December, the secret may be in finding a combination parasite/predator. A predator that subsists through the rest of the year either in hibernation or on the occasional early emergence, only to reproduce during the height of the shelf elf cycle, may be the only effective way to get populations into something approximating control.

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“Its structural perfection is matched only by its hostility.”

In some cases, while biological controls may seem to be the best option, the available biological controls may be organisms that may themselves become pests under the right conditions: for instance, Asian ladybugs becoming pests in vineyards when they feed on ripening grapes and taint the resultant wine. Sometimes the best option is to use several types of control organisms, especially when needing to ensure that one species doesn’t become a threat with increased numbers.

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Finally, one remaining option is now available due to advances in technology. A possible alternative to wiping out the shelf elf may involve introducing organisms that outcompete it for available resources, such as food or nesting sites. In many areas, the beneficial Bench Mensch has made inroads into shelf elf habitat, but future control may involve a combination of mechanical and biological controls. A competitor that can remain in hibernation for years or even centuries between shelf elf infestations, with an active resistance to retaliation, and a built-in weakness should it become a pest: the future is here.

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“Shiny and chrome!”

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Introducing Euphorbia flanaganii

Euphorbia flanaganii, the medusa head

At Triffid Ranch shows, one of the big draws, obviously, comes when I introduce passersby to the plants. All that I need to say is “Nearly everything here is carnivorous. Guess which ones aren’t.” Suddenly, it becomes a Gahan Wilson-designed Easter egg hunt, with everyone trying to see which plant didn’t consume flesh in its off time.

Euphorbia flanaganii, commonly known as “Medusa Head,” fools them every time. Between its tentacles and what appears to be multiple blunt-beaked mouths in the center, many of those passersby swear that it moves to follow them. When I have to admit that no, it isn’t actually carnivorous, they’re actually disappointed, because it makes an exceptional carnivore mimic.

E. flanaganii gets its common name from both its general reptilian appearance and the fact that it will grow to the size of a human head if left alone. It’s a member of what are referred to as medusoid euphorbias, a group of succulents native to South Africa. The entire Euphorbia genus is widely spread across the Old World, filling many of the niches filled by cactus in the Americas, and the variety of forms seen in the genus is simply breathtaking. E. flanaganii is one of many arresting oddballs, and it combines both ease in care with just a touch of danger. But I’ll get to that.

Euphorbia flanaganii
The structure of a typical medusa head is separated into the arms and the central caudex. As the plant grows, new arms form near the edges of the caudex, gradually spreading out as the plant grows, and the old arms shrivel up and die. Although a succulent, the medusa head needs much more water than would be acceptable or tolerable from most cactus or even most aloes, and it warns of a lack of water by gradually curling up its arms toward the center. It thrives under direct sun, and needs at least six hours of direct sun per day for decent health and growth. Best of all, once it’s situated and happy, it demonstrates its contentment with life by producing a ring of chartreuse blooms, each about the size of a ball bearing, around the caudex. The flowers don’t look like much under visible light, but they absolutely shine under ultraviolet lights.

Now, I mentioned “a touch of danger,” and that danger is why E. flanaganii shouldn’t be kept within easy reach of children or pets. The arms are tough and flexible, but if broken, they exude large amounts of latex sap. Said sap is about as toxic as that of other euphorbias: do NOT let it get in your eyes, and I highly recommend washing hands or other skin exposed to medusa head sap before getting said skin anywhere near your mouth. While none of the available literature mentions it, I’ve noted that the sap also has a phototoxic effect if it’s not washed off immediately. I had no reaction on my hand after getting some sap on my hand until I had no choice but to get out into the sun about an hour later. The resultant burn blister on the affected area taught me to wash my hands thoroughly afterwards.

On brighter subjects, E. flanaganii makes an exceptional container plant, and it can also be put into gardens so long as it’s protected from freezes. Even then, it’s remarkably tough. I had one head-sized flanaganii that I feared had died from exposure to the week-long deep freeze in Dallas in February 2011, and it didn’t make it. However, enough of the arms survived that they grew into new plants.

That’s the other bit of joy with working with E. flanaganii. Once it reaches a certain size, a mother plant will produce pups on the ends of older arms. The growth starts as a swelling at the end of an arm, and rapidly grows its own caudex and arms. After a time, if they don’t root on their own, the arm shrivels and allows the pup to roll away, where it rapidly grows if given access to soil and water. If you’re not careful, you can end up with a whole greenhouse full of them.

While they give no indication of ever becoming an invasive plant, medusa heads seem otherwise perfectly suited for North Texas conditions so long as they get watered regularly during the worst parts of summer. They don’t sunburn easily. They have no insect pests in the US, at least so far as I’ve noted, and even stink bugs stay away from them. They require good drainage, but they’re not fussy about soil conditions otherwise, and they grow well over a wide range of pH levels. They don’t seem to be susceptible to any parasites or diseases seen among other succulents, and they require only the occasional dash of fertilizer. Oh, and when mulched with Star Wars action figure parts, particularly Boba Fett and stormtrooper figures, people tend to go nuts over them.

Tiffany at ConDFW

— Many thanks to South African horror writer Nerine Dorman for turning me onto the joys of the entire Euphorbia clan. She and her husband have been raising South African succulents for years, and she’s forgotten more about the euphorbias than I’ll ever learn.

“I Can’t Believe I Ate The Whole Thing.”

The weather has been strange in North Texas, but not as strange as it was last year. That said, we’ve had odd fluctuations in both temperature and humidity, with mixed results among the carnivores. The flytraps and butterworts love the available prey, and they can’t complain about surprisingly cool mornings. The Sarracenia, though, are having a few problems, and it’s because they’re a little too good at their jobs.

One of the last things a wasp ever sees

For the uninitiated, this is the throat of a North American pitcher plant hybrid, Sarracenia spp.. For a lot of insects, this is one of the last things they’ll ever see. The hood on top secretes nectar that attracts everything from gnats to wasps, and the throat of the pitcher produces even more. On good days, you can actually see wasps hanging on with their rearmost pair of legs, desperately trying to keep their balance and not fall in. If they do, well, they aren’t getting out. The nectar contains a drug called coniine, getting the bug drunk in small doses and becoming lethal in large ones, so that only improves the odds that they’ll slip.

Unlike the other plants worldwide that garner the name “pitcher plant”, Sarracenia are a bit more aggressive in retaining prey. Sarracenia shares with its distant cousins a wide throat area lined with wax, so dislodged insects that lose their grips slide inside. Like their cousins, the throat is shaped so that any bug that tries to fly out finds that it’s actually pulled deeper into the plant’s trap. (This isn’t completely true, as some insects and their larvae regularly feed on larger relations that can’t escape. However, we’re talking about the majority.) About a third of the way down, though, the inside of the pitcher is lined with sharp and strong downward-pointing hairs, and I can attest from bloody experience as to their strength and sharpness. (Let’s just say that cutting a damaged pitcher in half lengthwise and running your finger the wrong way up the pitcher interior isn’t exactly like running your finger up a bandsaw blade, but the effect is much the same.) Trapped bugs get a choice: fight the flow of the hairs and get punctured, or keep going down. Ultimately, the bugs run out of “down”, and that’s when the plant secretes digestive enzymes and breaks down the doomed critter. The plant absorbs needed nitrogen and phosphorus, and the vermin census in the immediate vicinity is down by one.

Sarracenia heartburn

As just about everyone who ever keeps Sarracenia is concerned, the plants are absolute pigs. In particularly lively periods for bugs, the pitchers can literally fill to the rim, with insects falling in and then crawling right out over the corpses of their brethren. In more insidious cases, though, one can see these strange burn spots on the pitcher sides, looking as if someone took a lighter to the trap. Beginners understandably panic about a blight or other disease and start spraying, but the real reason is a bit more insidious.

Let's take a look inside, shall we?

To find out more, you have to give whole new meaning to “peeking under the hood”. With a gentle touch, it’s possible to bend the hood back and take a look inside. (Afterwards, wash your hands, and make sure that you don’t put your fingers in your eyes or mouth before doing so. I’ve never had a problem with coniine toxicity, but that’s probably because I don’t take risks with the same active ingredient that makes hemlock-cooked hot dogs so tasty.)

Sarracenia interior

And here’s the problem. The previous few days saw two major factors that affected this Sarracenia: ridiculously dry days and ridiculously moth-filled nights. The relative humidity outdoors reached as low as 15 percent, meaning that the plant couldn’t produce its digestive fluids as quickly as it would have liked. Since Sarracenia don’t have teeth or other structures to increase the surface area exposed to enzymes, the trapped moths, and there are a lot of moths down there, started to rot before the plant could digest them. If the rot is bad enough, it burns the inside of the leaf, working its way out, leading to those scars on the outside of the trap.

Now, this can happen in different circumstances, usually involving extremely low temperatures or lack of sunlight. In this case, it was caused purely by low humidity combined with especially intense sun due to that lack of humidity. (The sun was intense enough to give some of my cactus sunburn, and it helped keep me inside until dark.) Either way, the affected pitchers themselves will die, ultimately, but the portions that didn’t burn will continue to take advantage of the nitrogen bounty and pass that to the rest of the plant. By September or October, this will be a very, very happy pitcher plant.

As an aside, when watching Sarracenia in the wild or in collections, keep an eye open for other interlopers. When I was first exposed to Sarracenia when living in Tallahassee a decade ago, I noted the number of green tree frogs that camped out in the pitchers. It’s a very handy relationship for both plant and frog. The frog has a place to hide from predators, and prey comes to it instead of the other way around. The plant effectively gets a set of teeth, as the frog snatches prey too large for the plant to digest effectively and then uses the pitcher as a toilet afterwards. The plant certainly isn’t complaining about getting its nitrogen pre-chewed, and if the frog dies of natural causes, then the plant gets a bit more. Other animals will take advantage of the situation, particularly spiders, but you’d be amazed at the variety. I regularly get baby Hemidactylus turcicus geckos that stalk both Sarracenia and Nepenthes pitchers in search of an easy meal, and they also don’t complain about having a good hiding locale in the middle of the day. I’ll just start worrying when I find fence swifts and other lizards in there, too.

Peering upon Hello Kitty hell

So far as I can tell, and as far as the chronicler of Hello Kitty Hell can attest, almost nothing in this universe is too foul, too sacrosanct, or too pure to be turned into a licensing tool for Sanrio’s Hello Kitty juggernaut. And yes, I mean the term “juggernaut” in its original sense, as in “something that demands blind devotion or merciless sacrifice.” Ar-15 rifles, age-inappropriate halloween costumes, pipes, sex toys…I’m waiting for Hello Kitty-branded Mars rovers and thermonuclear weapons next.

I guess I shouldn’t be surprised that the Hello Kitty cult has infected gardening. And that’s fine. Really. Much like being one of the only businesses in the Dallas-Fort Worth Metroplex that hasn’t received a “Best of Dallas” award from D magazine (mostly because the main qualification for being one of the 783 entrants in each and every category, as announced every month, is paying for the advertising space), the Triffid Ranch is and will always remain Sanrio-free. No Hello Kitty planters, no tomato stakes, no terraria, and no cow manure compost. With the last, that would be redundant.

However, I can understand the appeal of attaching one’s products to an existing brand and running with it, hoping that this translates to business for the company’s other products. I just need to find something a bit more wholesome than Hello Kitty. You don’t think that Peter Jackson would have any issues giving a license for a line of Meet the Feebles garden gnomes, do you?

The Drooling Sundew

Contrary to the opinion of random passersby who want to come by at all hours “to look at the plants,” the Triffid Ranch isn’t a full-time operation. Oh, it’s a full-time operation, but it’s not the only jobs we hold. Especially during the winter, when all of the temperate carnivores are dormant and the tropical carnivores are resting, having a standard day job like everyone else is a necessity. Among other things, the day job provides health insurance, a steady background income, and a surplus of scintillant conversation from my co-workers. And no, I’m not exaggerating, because I work with a crew of truly unique talents, and we literally have no idea how much our mutual experiences can benefit the other. Ask the engineers circling the coffee machine about their weekends, and the responses sound more like plotlines to a remake of 2001: A Space Odyssey than anything else.

Anyway, compared to the professional musicians, semi-pro glassworkers, and enthusiastic amateur knifesmiths on board, my passion for carnivorous plants marks me as one of the Quiet Ones, and not the oddball in the back corner of the office who isn’t trying to drink himself to death every night. (And yes, I’ve worked in that sort of office. Remind me to tell you about my days working at Sprint one time.) Every once in a great while, though, I can fend for myself, and sometimes even bring something to the lunch discussions that leads to a good bout of Head Explodey.

By way of example, I recently brought a Cape sundew (Drosera capensis) to its current space in my cubicle, mostly because it was a needed touch of green next to a window full of brown. No, let’s be honest: BROWN. Even before the current freezing nights hit, everything was a uniform blasted tan out the office window from the drought, and it was about as pathetic and depressing as a Firefly marathon on SyFy. Indoors, under a good stout 23-watt compact fluorescent bulb in a desk lamp, that sundew promptly perked up and started throwing off new leaves, and I fully expect for it to demand full rights from the UN by spring.

That little sprig of green got more than a few questions from co-workers and project managers, and the first question was “When are you going to feed it?” Since I knew that they’d be less than thrilled by my bringing in a tube of wingless fruit flies, I decided to demonstrate the one commonality between carnivorous plant and human: an appreciation for chocolate.

In his classic volume Insectivorous Plants, Charles Darwin understandably went a little crazy in his enthusiasm over Drosera of all sorts. This book details most of his experiments in understanding sundew mechanics and responses, and he discovered that sundews respond to two different stimuli in different ways. Firstly, the long sticky hairs (officially called “tentacles”) were sensory hairs in that they picked up the movement of prey caught in their glue, and consistent movement of one tentacle caused others in its vicinity to converge on the area, further trapping that prey. Secondly, specialized glands at the tip of each tentacle could ascertain the relative nitrogen content of the item trapped. If the stimulus was something relatively non-nitrogenous, such as a grass stem rubbing against the sundew’s leaf, the tentacles might respond, but the plant wouldn’t try to digest the intrusion. If the stimulus was high in available nitrogen but unmoving, such as a dead bug landing on the leaf, the tentacles wouldn’t respond right away, but they’d ultimately detect the morsel and move to claim it. And chocolate? It’s sufficiently nitrogenous that a sundew might mistake small pieces for gnats or other tiny insects, but without rotting or growing mold while digestion took place.

One of the reasons why D. capensis is perfect for this demonstration is that it’s one sundew that’s singularly enthusiastic in its feeding response. It doesn’t close on prey as quickly as some Drosera species, but its entire trapping surface wraps around prey, sometimes completely surrounding it. Even better, D. capensis‘s output of digestive enzymes is not just visible to the naked eye, but it’s voluminous. Put a mosquito on a Cape sundew leaf, and you get more puddling drool than a doorbell in the Pavlov house.

Anyway, since one of my favorite co-workers asked to see sundew trapping behavior, I pulled some leftover dark chocolate Halloween candy from the department stash (since it’s in a Halloween cardboard display, it’s referred to as “the candy coffin”), scraped off some crumbs, and sprinkled them on the sundew’s leaves. She was a bit disappointed by the immediate response, as she expected something more energetic. “Patience,” I said, “you have to give it some time. If that chocolate was moving, we’d see much faster movement, but it’s still not something you can see in a few seconds.” We left it alone and continued through the day, checking back every once in a while to verify the chocolate’s status.

This morning, my friend came in shortly after I did, and immediately visited the sundew. That’s when she viewed this.

Drooling Cape sundew (Drosera capensis)

Another reason why Cape sundews are great subjects to demonstrate active trapping behavior is that they’re extremely active compared to many other good beginner’s sundews. Note the several folded leaves, where the trapping surface actually folded in half to surround the chocolate. Even better, notice the one on the right that’s curled like a fern fiddleback? That one caught a chocolate crumb near its tip, and the shine down the leaf is digestive fluid. Yes, like most people, Cape sundews drool like fiends when given chocolate.

And now the obligatory disclaimer: I do NOT advocate feeding Cape sundews chocolate on a regular basis, and I definitely don’t recommend it at all for most sundew species. Don’t even think of doing it for most other carnivores. More importantly, as with people, the best results with sundews come from reasonably fresh dark chocolate, so spare the poor plant that dried-up Hershey’s bar that’s been in your desk since 1998. Absolutely importantly, keep the feeding to crumbs: your plant and your co-workers will hate you if you drop a whole Godiva’s truffle in the sundew’s container. As for everything else, anyone have any high school-age kids who want a science fair experiment on sundew sensitivity to different varieties and brands of chocolate?

Absolute Surefire Steps to Kill Your Venus Flytrap: Step 5

Curious about the context? Check out the introduction.

Some of the content in this series appeared, in much shorter form, in Gothic Beauty magazine.

Step 5: Set off its traps with your finger.

Home improvement stores are dangerous places to be when you’re married to the Czarina. On any given day, she has one interesting project or another that’s cooking, from making new necklace displays to building mobile bead tray racks, and that means the folks at the local Home Depot and Lowe’s stores know us on a firstname basis. If she’s not buying up PVC pipe and walnut molding, I’m buying up epoxy putty and Gorilla Glue. What’s scary is that I can exclaim, in my best Red Green voice, “Today on Handyman’s Corner, we’re going to reverse the polarity of the neutron flow!”, and I hear loud and robust laughter from the checkout clerks. At our local traditional hardware store, I had to explain who Red Green was, and this was a store that was hosting an autographing and photo session.

Anyway, I tend to wander through the garden section at those big stores as well. Most of the time, it’s to rescue some poor neglected Dendrobium orchid or random succulent in the deep discount rack, but every once in a while, it’s to see the latest trends in carnivorous plant packaging. Not in variety, nor in propagation methods, but in packaging.

As mentioned a while back, my father was, before he retired, a packaging engineer of some reknown. Every time you see one of those aluminized Mylar packages of Doritos or Fritos in an office cafeteria vending machine, you’re looking at my dad’s work. As also mentioned a while back, the family was hoping that I’d be another Larry Ellison instead of a Harlan Ellison; not much rubbed off from the family’s fascination with engineering. However, just enough rubbed off that I can appreciate the commercial horticulture trade’s attempts to protect its Venus flytraps.

One night, I saw a beautiful example of this in action. I was in a Home Depot picking up some extra garden hose gaskets, and peeked in the garden section. That section was hosted by a girl who was maybe 19 if a day, and she was standing in front of a big rack full of Venus flytraps. These were in those sad plastic containers that were popular at the time, with one clear dome atop a flimsy clear cup, and she was popping them open one at a time. I stepped closer, and I realized she was setting off every trap on each plant with her finger. Once every trap was closed or closing, she recapped the cup and moved on to the next one, and when she saw me, she waved me over. “Watch this,” she said, as she set off another trap.

At that point, I winced. “You really shouldn’t do that. That’s not good for the plant.”

“Oh, it doesn’t hurt it,” she said, going back to molesting the flytraps. Seeing from her badge that she was the garden center manager, I decided that arguing with her was a waste of time, and I simply left.

Right there, with that manager, the entire fascination with flytraps stands revealed. Here is a plant that closes up mouth-like traps, not under any touch such as with Mimosa pudica, but under the specific stimulus of setting off trigger hairs within the trap. The Venus flytrap can count and keep track of time, as the trap won’t close unless two of those trigger hairs are set off at the same time or one is stimulated twice within ten seconds. Even better, if the trap was triggered by something inedible, such as a raindrop or a twig, or by something too big for it to catch and hold, the trap gradually re-opens over the space of hours or sometimes days.

Well, that’s the popular legend, and it’s all true. It also leaves out a lot of particulars that can kill the plant if ignored.

Firstly, when looking at a Venus flytrap, it’s easy to see the trap as something growing off the end of a leaf. In actuality, the trap is the leaf, and the “leaf” is actually what’s called a petiole. Although the leaf’s secondary adaptation is to catch and digest small prey, it’s still a photosynthetic surface, no different from a maple leaf in that regard. The reason why flytraps just sit there and wait for prey is because, like all other plants, they’re relatively low-energy organisms compared to animals. They can afford to wait because their main source of energy comes from the classic conversion of sunlight, carbon dioxide, and water into sugars and connective tissue.

What this means is that if a trap gets set off with prey inside, the plant benefits from the nitrogen and phosphorus in the bug being digested (possibly along with trace elements, but I haven’t found any research to ascertain what else they may absorb), but the actual photosynthetic surface of the leaf is out of commission until the digestive process is complete and the trap re-opens. If the trap closes without capturing prey, yes, the trap will re-open. The problem is that the return on captured nitrogen just barely makes up for the energy expended in re-opening it, and an empty trap doesn’t even get that. Close enough traps at the same time, and wondering why the plant dies is like holding you down, clamping your nose and mouth shut, and wondering why you’re turning purple.

Incidentally, this also ties into a regular complaint I hear about how “my flytrap won’t eat.” The closing process is a very ingenious use of topography, but opening is a simple growth process. Picture it as opening a mostly-closed door by shoving wedges into the crack between hinges until it pops back open. Add enough wedges, and the door can’t shut at all. After a flytrap’s trap has been set off about four or five times, the trap curls slightly and now acts as nothing but a photosynthetic surface. In that regard, it’s perfectly suited for its job, but no force on earth or heaven will get that trap to close ever again.

This doesn’t explain why flytraps kept in colder conditions, such as those going into winter dormancy, are so loath to close, but it doesn’t have to. Between lower temperatures and lower light levels during winter, any trapped prey in a dormancy-bound flytrap will rot before it ever gets a chance to be digested, so don’t worry about feeding your flytrap over the winter. Giving it plenty of light before snow or ice kill off the current year’s traps is good enough.

Next: Step 5 – Feed it hamburger.

Absolute Surefire Steps to Kill Your Venus Flytrap: Step 4

Curious about the context? Check out the introduction.

Some of the content in this series appeared, in much shorter form, in Gothic Beauty magazine.

Step 4: Keep your flytrap in a terrarium.

I have a lot of reasons for hyping fellow carnivorous plant sellers, besides the idea that we’re all in this together. I view Jacob Farin and Jeff Dallas of Sarracenia Northwest as the crazy cousins I never had (well, I have crazy cousins, but not horticulturally inclined crazy cousins), and I enthusiastically turn friends and cohorts in the direction of northwest Oregon when Jacob and Jeff host one of their biannual open houses. This isn’t just because they know their plants and obviously love them. It’s because they’re constantly challenging me. In my old age, I’ve become more convinced than ever that it’s better to be correct than to be right, and they’ve taught me too many times to shut up, listen, and make sure that any questions I ask or comments I make weren’t already answered a week ago. (They also have better stories. I only have to worry about treerats digging up the dragonfruit and geckos hiding in the pitcher plants. They get Pacific treefrogs laying eggs in their aquatic bladderwort tanks and piglets sneaking through the fence from their neighbor’s lot and playing in their lot. The only way I’m ever going to top this is by getting that crocodile monitor after all.)

Anyway, the Sarracenia Northwest tagline is “No terrariums. No myths. No nonsense.” It’s succinct and accurate, and one of the reasons why Jacob and I may be found by palaeontologists 90 million years from now, still locked in combat like the Mongolian fighting dinosaurs. It’s not that he’s wrong. He’s just lucky in that he and Jeff live in a locale where humidity levels aren’t so obscenely low.

One of Jacob’s tenets is that most carnivorous plants can and should be grown outside, in full sun, just the way they do in the wild. He also posits that most carnivores are much tougher than most people assume, and that most adapt to outdoor life much better than expected. He and Jeff offer living proof at their open houses, with growing pools just overloaded with big, bright, sparkly Sarracenia that make my guts ache with jealousy to look at them. Flytraps, bladderworts, and even their beloved Darlingtonia cobra plants…all outside, or maybe under fabric covers if the plant is particularly sensitive to strong summer sun.

To give you an idea on their commitment to researching proper growing traditions, they went into the wild to visit feral stands of Darlingtonia. Tourists may know of the Darlingtonia State Natural Site southwest of Portland, but Darlingtonia californica can be found among seeps throughout the mountains of Oregon, Washington State, northern California, and parts of British Columbia. Darlingtonia is one of the big El Dorados in the carnivorous plant field, having a reputation for being particularly temperamental and likely to die if you look at it cross-eyed. In fact, one of the absolutes that was taught to most carnivore enthusiasts, myself included, is that they can’t handle heat for any length of time. Jacob and Jeff decided to challenge this, taking temperature measurements in prime Darlingtonia habitat and showing that Darlingtonia can handle Dallas-like daytime temperatures in daylight hours with aplomb. (The secret to raising Darlingtonia is that it’s technically an alpine plant, and that it grows in seeps in the mountains fed by snow melt. The assumption was that it needed cool water on its roots at all times: the real issue is how cool the area gets at night. In North Texas, that means lots and lots of air conditioning, because it depends upon the steep temperature drops in the mountains at night, even during the summer.)

This has led to many friendly arguments about whether terraria should ever be used for carnivores. Jacob in emphatic that terraria aren’t necessary, and that he has customers who raise bog gardens in the desert and get great results. I respond that as much as I agree with him anywhere else, some carnivores can only survive in Dallas in an enclosed container. Not only do we receive almost twice as much sunlight as Sarracenia Northwest gets, due to the SN nursery being above the 45th Parallel North, but we also have a dessicating south wind that stops only between October and March. Even on good years for plant-raising, the area regularly drops below 50 percent relative humidity. In bad ones, such as this year, Dallas has lower relative humidity than Phoenix.

Now, you may ask yourself “What does this have to do with the price of cheese?” It’s time for another digression, and a short one this time. Back in 1985, I picked up a 29-gallon aquarium at a garage sale, and promptly drove everyone around me insane with my sudden passion for freshwater tropical fish. While co-workers were sneaking home to read Hustler before their wives and girlfriends caught them, I was sneaking home with the latest copy of Tropical Fish Hobbyist before my roommates knew what I was planning. In the process of learning just enough to be dangerous (and this included keeping, for a very short time in Wisconsin, a red-bellied piranha named “Bub” that would come to the surface to get his nose rubbed), I noted that different authorities gave different advice about the same fish, sometimes in the same book or magazine. That’s when the owner of the sadly defunct shop Neenah Tropical told me “You should never trust the books, because the fish don’t read.”

That’s absolutely true for carnivorous plants, as well. Always take my or anybody else’s advice on keeping carnivorous plants with a healthy skepticism born of actual knowledge. Those of us with expertise will try our absolute best to help, but there’s always the odd exception. If you’re smart, you’ll accept the unique conditions and circumstances in your area that allow success when everyone else falls on their faces. For years, I was able to keep a batch of Darlingtonia raised from seed alive and healthy in Dallas, and I didn’t smirk about how I had special understanding or superpowers. Instead, I stood back and exclaimed in surprise and delight that I’d somehow beaten the odds. And when this kidney stone of a previous summer took them away from me, I took it as an object lesson.

And here’s where I have my very friendly dispute with Jacob and Jeff. I don’t dispute that Venus flytraps are best kept outside. At times, though, they need a touch of help.

In my own experience, I’ve discovered that flytraps grow best when the relative humidity around them stays, day and night, above at least 60 percent. When the humidity goes below 50 percent and the temperatures go above 95 degrees F (35 degrees C), they tend to produce small or nonfunctional traps, and won’t produce new ones until either humidity jumps or temperatures drop. When the temperatures stay this high and the humidity drops below 30 percent, which it did quite regularly in North Texas last summer, the plants simply can’t handle the strain and they die. It doesn’t happen right away, and they can recuperate if conditions improve when they start to fade.

Since a typical Wardian case offers that sort of control, the automatic response to this sort of humidity fluctuation is to put flytraps into a terrarium of some sort. As understandable as this is, this is also dangerous for a flytrap. What I’ve discovered the hard way is that flytraps not only require a lot of sun (at least six to eight hours of direct sun) and a lot of humidity, but they also require a LOT of air circulation. This is why Jacob and Jeff recommend raising flytraps outdoors, where they can get the air circulation they need. Put one in a standard terrarium, and the combination of stagnant air and decreased light intensity are doubly lethal.

A second consideration: even if your flytrap does well during the summer, remember that it’s going to need a winter dormancy period. This leaves you with one of two options. You can put the terrarium outside during the winter, which removes any opportunity to enjoy it during the season where you’ll need a touch of green the most, and risks its being damaged by cold or ice. Alternately, you can remove the flytrap and put it into artificial dormancy in a refrigerator, and then spend the winter looking at the hole in the terrarium where the flytrap used to be. Instead, you might be better off enjoying a tropical carnivore such as a tropical sundew: it may slow down over the winter, but it won’t actually require a full dormancy.

A third factor to consider against a standard terrarium: since the air circulation is so poor in most smaller, seemingly flytrap-friendly terraria, putting one in direct sun is a great way to produce Venus flytrap pottage. Terraria, Wardian cases, greenhouses, and just about any other enclosed space can be used to demonstrate the square-cube law. The smaller the volume, the larger the surface area in proportion to that volume. Put a 100-foot greenhouse in the sun as a two-cup terrarium, and the terrarium reaches killing temperatures much faster.

At this point, you again have two options. You could fit your Wardian case with a solar-powered fan, thereby taking care of the immediate air circulation issue. This, though, does nothing about the dormancy situation. Or, or, you could try a container that helps simulate the best conditions for best health for a flytrap. I’ve discovered that large glass bowls, such as very large brandy snifters or even goldfish bowls, tend to work well in combating Dallas-level low humidity. The container can be put in full sun, where excess heat escapes out the top. Humid air is heavier than dry air, so the humidity stays around the flytrap. Best of all, it can be left outside all year, only pulling it under cover when there’s a risk of snow or ice.

I’d be lying if I didn’t say that there was one more catch. This catch is that while flytraps like moist conditions, they cannot handle standing in water for any appreciable length of time. With that in mind, if you try a large bowl, go for one that’s strong enough to handle the peat/sand mix that’s required for flytraps. Again, many experts recommend against using perlite around flytraps under any circumstances, but I’ve found a layer about one inch (2.54 cm) on the bottom, followed by about four inches (10.16 cm)of equal parts milled sphagnum peat moss and high-quality silica sand, works best. Dress the top with long-fiber sphagnum, wet everything so that it’s moist but not soggy, and plant the flytrap on top. Under most circumstances, flytraps in this sort of enclosure seem to do much better during dry summers than unprotected flytraps, and MUCH better than ones in greenhouses or other covered enclosures. But that’s just me.

Next: Step 5 – Set off your flytrap’s traps with your finger.