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Plantgasm - I love plants too much. By Derek Powazek.

Sex in the Garden: Tongue Orchids and their Dupes

You already know that orchids have pretty freaky sex lives. They depend on insects to carry their pollen from one flower to another, and employ a number of techniques to entice the bugs to visit. It turns out, some of those techniques are more successful than they need to be.

Take the Australian tongue orchid (Cryptostylis). The color, shape, and smell of its flower mimics a female wasp, so the male is attracted to it. Its pollinator is the Lissopimpla excelsa, or “Orchid Dupe Wasp.” (Imagine being named after your least complementary trait! Poor dupe.)

But here’s where things get interesting. In a study published in The American Naturalist in 2008, researchers found that most of these orchid-wasp pairings resulted in a “happy ending” for the pollinator. Yes, they found ejaculate in most of the flowers.

(Let’s just pause here for a moment to think about people collecting wasp spooge from orchids for science. Great job.)

The study claims to be “the first conclusive evidence of insect ejaculation in response to floral stimuli.” And they proved that these orchids have a far higher pollination rate than other orchids because of it.

This revelation led to some fascinating questions. If Dupe wasps are wasting all their valuable sperm in flowers, doesn’t that mean the female Dupes are left wanting? And wouldn’t that lead to an inevitable decline in the wasp population? And if these wasps are the only pollinators for the Cryptostylis orchids, how can they survive? Thankfully, nature always finds a way.

It turns out the Dupe wasps are haplodiploids. That means that, in addition to mating the old fashioned way, the females can also produce offspring all by themselves. When they do, those offspring are always male. So the orchids lure the male Dupes away, and the female Dupes just make more. Nature is clever, if not always kind.

Want more Sex in the Garden? Check out these fine posts from my fellow Bay Area Plant Bloggers, who all have sex on the brain today.

Photo from the study, copyright Esther Beaton.

I Always Feel Like Somebody’s Watching Me


My Pleiospilos nelii, aka Split Rock plant, is watching me.

Nasty, Nice Nasturtium

Speaking of plants some consider to be weeds, Nasturtium (which is actually Tropaeolum*) is a South American native that you can find growing everywhere in San Francisco. I’ve seen Nasturtium vines engulf whole bushes, spread over an entire park, and possibly abduct children. I pulled this guy out of a pot yesterday, where he sprung up almost overnight. You can still see the seed that started it all.


That’s the neighbor’s dog, Brutus, making a cameo in the background.

So Nasturtiums are nasty because they can be quite aggressive. But they’re also nice! Their leaves can get as large as dinner plates. In a dense thicket, they look kind of like lily pads in midair. The whole plant is edible, too. Their flowers have a crunchy pepper quality that makes them great salad toppers.

Personally, I love Nasturtium. It’s not their fault they thrive in their new environment. I came from another place, too. So I took the one in the photo above and planted him in his own pot. Everybody needs a place to call home.

corona heights north slope trail

* The plants I’ve always called “Nasturtiums” are actually the genus Tropaeolum. There is a genus called Nasturtium, but it doesn’t include them. So Nasturtiums aren’t Nasturtiums. See, this is why nobody knows plant names.

Masdevallia floribunda flowers

Masdevallia floribunda

It’s always exciting when an orchid flowers for the first time. When I got this little guy at the Pacific Orchid Expo, he was already mounted on a little bit of wood, but he wasn’t yet blooming, so this is the first time I’ve gotten to see his flowers. They’re adorably tiny.

If Loving Arum is Wrong, I Don’t Want to be Right

This post is going to have so many important disclaimers, I decided to put them first.

Disclaimer 1: Technically, everything in a state/city-owned park is owned by the state/city, and removing anything is either against the rules or outright illegal, unless you have permission, which I got from a gardener who told me I’d be doing him a favor removing the Arum since he considers it a weed (see disclaimer 2).

Disclaimer 2: The Arum genus is invasive in some places. Some gardeners curse the plant as a horrible pest. I’m not one of them.

Disclaimer 3: Arum, like most Aroids, are poisonous and contain calcium oxalate, which can irritate the skin, though I’ve never had a problem handling them.

Got all that? Okay, then.

I’ve been keeping an eye on a few clumps of Arum (probably italicum) in Buena Vista Park all year. I love their arrowhead leaves with silver lines, and their spathe/spadix flowers. I noticed them blooming way back in March. They’re a beautiful bit of the tropics here in California.


If their flowers are fertilized by flies and ground-crawling bugs, they form berries. They start out green, then turn yellow, and then finally red when they’re ripe. This is a signal for birds to come eat them, and in turn “distribute” (aka poop) the seeds elsewhere.

Buena Vista Park is where I walk my dogs, so it was easy for me to keep an eye on them. I first noticed the green berries in April, and they started turning red in late July. Four months is a long time to survive in a dog park.


When I finally saw red berries, I harvested some (see disclaimers!) and took them home to plant. Preparing Arum berries is like other Aroids, including Alocasia and Pinellia. Each berry contains a seed or two, which you have to pop out and wash. Aroid seeds aren’t viable for long, and they die once they dry out, so the quicker the better.


Once you pop the seeds out and wash them, you can plant them like any other seed. I put mine in a few pots, in normal houseplant soil, buried a quarter inch or so. If they sprout, I’ll plant them somewhere they’ll be appreciated, like my back yard, where the Buena Vista Park gardeners can’t find them.

They Are Hugging


I grew carrots for the first time this year and wasn’t sure how they’d do. So, I have to admit, I sewed the seed into the garden bed a little thick, and I never bothered to thin them out. As a result, the carrots aren’t exactly pretty. Still, they’re tasty. And this pair came out looking especially fond of each other.

Orchids and Freaky Moth Sex in Chiang Mai

I visited Thailand in April with a group of garden writers. The trip was sponsored by the Tourism Authority, but as they say on NPR, the opinions expressed are those of the author, not the underwriter.

Our first stop in Chiang Mai was Bai Orchids, where we got a demonstration of orchid propigation by an elderly master gardener. He was a little difficult to understand, but his passion for the plants read loud and clear. I have him to thank for getting me started on bottle orchids as well as trying to pollenate my own.

I wandered the rows and rows of orchids I could never grow outdoors at home in San Francisco. There were Vandas that were taller than me. I was particularly captivated by the dense forest of their roots.

But nothing in Thailand is ever just one thing. So in addition to being an amazing orchid nursery, Bai is also a butterfly farm. An enclosed area next to the orchids was home to thousands of butterflies, dragonflies, and moths. In one spot, I saw the largest moth I’d ever seen – about the size of my hand, fingers outstretched. As I was photographing him, I noticed that he was not alone. Behind him was his, um, good friend, with whom he was intimately connected.

Orchid sex and moth sex, all in one place? Thailand is awesome.

I Definitely Impregnated My Phalaenopsis

A couple weeks ago I said, I Think I Impregnated My Phalaenopsis. Check it out today.

That’s an affirmative. Grow, pod, grow!

Garden Links for 14 July 2011

We read the botanical web so you don’t have to. In this edition: trash, Alcatraz, crime, and weed.

Dracaena at the Doctor

When some friends of mine asked me what was wrong with one of their houseplants, I said to bring it by and I’d take a look. I had no idea they’d be showing up in a truck. They unloaded a tree that’s taller than me. As you can see, it’s in a bad way.

the patient

Based on the look of the stems and an old photo, I think our patient is a Dracaena marginata, which Mr. Subjunctive wrote a thorough profile of a few years ago.

When I grabbed the plant to move it, the trunk was soft. Soft is bad. You can also see that some of the upper stems have just bent right over. The plant’s owners told me they’d moved it into a sunnier spot a while back. There may have been some overwatering, and then some underwatering. I tried to break the news gently.

My friends, this tree is dead. Dead as a doorknob. Dead as disco. Really, really dead.

But there’s hope! Because as my Dracaena fragrans proved, Dracaena can be rooted from cane cuttings. And some of this patient’s tips were still green inside.


In the bottom, left photo, you can see the obvious difference between a dead cane and a live one.

After a little exploratory surgery, I was able to take six mostly healthy-looking cuttings. My previous attempts to root Dracaena cuttings in water have been pretty successful, so I placed them all in water. I’ll be able to see if roots develop.

We may have lost the patient, but if the cuttings root, the plant will live on.


Plantgasm is where Derek Powazek chronicles his botanical antics and misadventures. More.