Monday, April 19, 2010

Random plant event: white-flowering Glechoma hederacea

I like Creeping Charlie. (Glechoma hederacea; also called ground ivy, gill-over-the-ground, hedgemaids, robin runaway, and alehoof; the botanical name is sometimes Glechoma hederaceum, as well, which is how I learned it originally, and which I'm still liable to revert to if I'm not paying attention.) I like it rather a lot, actually. I understand why some people wouldn't -- it disrupts the smooth, even green of a perfectly-manicured lawn, and for some reason, perfectly-manicured lawns of a single color are what you're supposed to have. Creeping Charlie makes them look scruffy, discolored, unkempt, whatever. And it's even worse in vegetable gardens or perennial gardens: it spreads. And spreads. And it's a noxious invasive that disrupts ecosystems and makes the baby Jesus cry. So fine. But I like it anyway.

This is almost certainly a childhood thing. When I was growing up (until the age of 11), we had a fairly large property, which was bordered by a row of walnut trees (probably Juglans nigra?) on the west and then had a giant weeping willow (Salix babylonica) immediately to the east of the walnuts. Between the walnuts and the willow, essentially no light reached the ground, and consequently, nothing much grew there -- except for Creeping Charlie. Which I didn't know was Glechoma at the time; I just knew it was really pretty when they all exploded in flowers all at once, that otherworldly luminous blue-purple that was dizzying to walk on.

Anyway. It's very noticeable right now, because they've all burst into flower within the last few weeks, and I've been trying to get a good photo of it for the same period, which means I've been looking for it in people's yards. And I happened on a batch of it in somebody's yard here in town (across the street from the Prunus cerasifera in yesterday's post, in fact) that had white flowers instead of blue-violet. Which I thought was interesting enough to share.

I've also discovered, on-line, that there are variegated versions of Creeping Charlie too, which are apparently just as invasive but slightly more decorative.

Amazingly, Glechoma is not on the Iowa list of noxious weeds (it is on Connecticut's -- no other state has bothered, nor the U.S. federal government): I find this kind of shocking, just because there were soooooo many people in the garden center when I worked there looking for something that would kill it. One of the first things I learned there, in fact, was where the Creeping Charlie killers were.

According to dkm65 at, it's "irresponsible to plant or encourage" Glechoma, which is probably true. PlantGirl1982 has stronger feelings about it still, and uses lots of exclamation points to express them.1 Jaimee cuts straight to "the most evil weed in the world."2 [shrug] Probably.

I've wondered whether it would work as a houseplant. Probably, right? I mean, if it can grow everywhere else. A lot of your easier houseplants are invasive outdoors, in habitats similar to their native ones. Also some of the older houseplant books include it. I'm tempted to try. Would it need a cold, dry, dormant period like a lot of plants here do?

Hmmm. If nothing else, having some inside the house would mean I don't have to feel bad about pulling up any that's in the yard, and I don't think it counts as irresponsible if the only way it can leave the house is by me taking it out of the house.3 We'll see. Maybe. I'm serious about being tempted.


1 ("All you creeping charlie lovers are crazy! This is a noxious weed! It should not be used for anything! Who cares if it is a groundcover, there are a lot nicer plants available for that purpose! It is a disguisting weed that makes its way over from your neighbors yard and creeps into you lawn." [sic])
2 Technically, Jaimee says it ties with Bermuda grass as most evil weed in the world. But tied for most evil is still pretty darn evil.
3 (Or tornado. I suppose it could get out if there were a tornado, too. But it's kind of silly to worry about it getting out, when there's so much already out there.)


Unknown said...

I just found your Blog. You crack me up! You are writting about a weed, right? That is a true nature lover right there...ha ha ha...(sorry I am slightly mad, I have just spent weeks weeding a patch of clay, which is some day going to be a our garden, and yes, some weeds are beautiful, but right now, I hate them all!)

Jeane said...

My mother had a trailing indoor plant she called creeping charlie. She had it for at least a decade, and it was quite pretty (but never sported flowers). I'm not sure if it's the same plant as the one you're describing, though.

mr_subjunctive said...


It was probably either Pilea nummularifolia or Plectranthus nummularius. The flowers on Pilea are small and sort of odd-looking; Plectranthus has pretty spikes of white or purple flowers but won't produce them if it's not getting bright light.

We can't actually rule out Glechoma hederacea entirely, 'cause as I said, it's in the houseplant books -- somebody must have grown it indoors at some point or another. But the other two are more likely.

Ivynettle said...

I'm quite glad that Glechoma is native here, so I don't have to feel bad about liking it - I'm the same way, love the way it turns lawns purple. And it's a pretty plant even close up.
And as a weed, well, it may spread, but I've never found it hard to pull up.
I've seen the variegated form, but never a white one. Pretty cool!
As far as keeping it indoors year-round, we had the variegated one at my ex-job (it was meant as a "mother plant" for cuttings, apparently they can be used for flower boxes) at about 18°C - warmer in the summer, of course, perhaps a bit cooler in winter, can't quite remember if we lowered the temperature... maybe to 14°C, certainly not lower, and definitely no dormancy.
In fact, I don't think it really goes dormant outside, either. Might freeze back in a really cold winter, but I think most years, it stays green even under the snow.

mr_subjunctive said...


Well, I took three pieces of the white and three pieces of the purple today, and potted them up, so we're going to find out how they do in a semi-normal home situation.

About a third of the commenters say the same thing: it may be invasive, but they don't have any problem keeping it under control by pulling it up. I didn't study the locations carefully, but had the dim impression that the further north you are in North America, the more you're likely to hate Glechoma.

Don said...

That's cool, Mr Subjunctive, spotting that white-flowered variety. I've never heard of such a variety.

Consider the usual things said against invasive exotic plants---I won't disagree. Still, I've always liked the look of ground ivy. And though some find the strong smell offensive, I've always enjoyed it---try rubbing a leaf.

State noxious weed lists are usually designed around the needs of the agricultural industry. States have only recently been developing invasive plant lists, whose concern is the degradation of existing ecological communities. Even so, those lists fall considerably short of being definitive, and the criteria for inclusion vary a great deal from state to state.

Piggyback plant (Tolmeia menziesii) and strawberry begonia (Saxifraga stolonifera) are the only two plants I can think of off the top of my head that are hardy here in USDA Zone 6 and are also useful houseplants. So I guess Glechoma hederacea is a third.

"... and for some reason, perfectly-manicured lawns of a single color are what you're supposed to have."

The reason's simple. Before the introduction of broad-leaved herbicides, lawns were expected to include a tapestry of grasses and broad-leafed plants, and people appreciated the look. Lawn seed mixes routinely included Dutch clover, which fixes nitrogen and fertilizes the grasses. After the end of WW2, when they introduced broad-leaved herbicides, Monsanto and Dupont cleverly created a shift in taste by manipulating the pressures that middle class homeowners place on their neighbors to "eliminate weeds." You can't eliminate the "weeds" without also eliminating the clover, so in addition to repeated applications of herbicide, repeated application of nitrogen became necessary. This is good for the chemical manufacturer's bottom line, but bad for the environment and the lawn-owners' wallet. And to those of us who grew up looking at grass monocultures, anything else now looks untidy.

I've been maintaining a small grass-clover lawn for some years now, and over time my eye has begun to appreciate the variation in texture, to the point where regulation grass monoculture lawns look boring. I've been consciously cultivating this change in taste, because I don't like the kind of manipulation that established my original esthetic unconsciously, and because of the tremendous environmental challenge we're facing.

Tigerdawn said...

Is this the same thing as henbit? I'm in OK and I've always called the purple stuff henbit. Whatever it is, I love it too. It makes the ground pretty and purple and then it's gone the next time you mow.

James David said...

I don't mind having these violet flowers in my garden - weed or invasive or what not - they still look pretty to me.

Lee said...

Glechoma hederacea 'Variegata' is sold as houseplant in South Korea. It is called 'Ssuk-hyang(which means, 'mugwort scented')' by nursery owners, though there already is a korean name for the species, 'Byeong-kkot-pul(weed with bottle shaped flower)'. The species is used to treat urethral and vesical calculus in traditional medicine, though I highly doubt it's effectiveness. It is common plant in countrysides, but hard to see in Seoul(except the variegated cultivar) due to overcollection and lack of suitable habitat.

Jeane said...

I looked at your photos, pretty sure now what she had was Plectranthus nummularius. It looks very familiar, and I know it was easier than pie to propogate with cuttings in water, or by winding them stem around inside the pot it would root itself again. Sweedish ivy, huh.

Emily said...

It looks kind of like what we called honeysuckle when I was a kid. The plant part looks the same. The flowers were on the pink purple side rather than blue, though. But you could pull the flowers out and at the bottom was a bit of nectar which you could bite off. We'd forage for honeysuckle in places where we thought it was unlikely there was risk of urine/pesticide residue.

Lance said...

I've always loved it here, but it seems like it comes up early and blooms, but when people mow for the first time in the spring, I never see it again for the rest of the year.

I kind of agree about yards being boring. My family has a place in the mountains in New Mexico. We've always maintained the 'lawn' as more of a natural look there. Meaning what we've planted has always been native flowers, and never mowing or spraying anything. It's always rewarded us by being beautifully green, and full of flowers.