Friday, July 4, 2008

Ghost (Hedera canariensis)

Hedera canariensis (Algerian ivy) is a lot like its close relative Hedera helix (English ivy), and has most of the same qualities, both good and bad. The most obvious difference is that it has much larger leaves than H. helix, but there are a few other differences as well.

When you do a search for this plant, most of the sites that come up involve outdoor cultivation. It's apparently pretty low-maintenance, and hardy in a lot of places (there's disagreement about the exact range possible: everybody agrees it will grow in zones 8 and up, and everybody agrees it will die in 5b or below, but anywhere between 6a and 7b is debatable, I guess. Also variegated varieties are said to be less cold-tolerant.), and it's pretty pollution- and salt-tolerant, I guess, as well. Also people usually note that it's from northwest Africa (also Portugal and the Canary Islands -- hence the name -- and that general region).


And then tucked in there somewhere will be a one-sentence acknowledgment that, oh yeah, it can be grown indoors too, which is usually as much information as you get.

I bought one in February 2007, and we actually got along pretty well for quite a while. I was a little worried about it, because of how plants in the Araliaceae are susceptible to spider mites, and I was, at the time, already dealing with a mite-y Hedera helix. But it turned out to be okay, even after the H. helix succumbed (to either the spider mites or to my efforts to rid it of spider mites; it's a toss-up which was the bigger problem), and everything was good for several months.

Hedera helix 'Gloire de Marengo,' R. I. P.

Then I started working in the greenhouse, in August, and shortly there were a lot more plants coming home with me, and things got a little crazy. Less time spent caring for the plants, or even looking at them, and then the blog started in October and things were even crazier. It wasn't a good time to be one of my plants (unless you were new). And at some point around mid-October, I noticed that the Hedera canariensis was looking a little off, a little dusty, but I looked at it a couple times and didn't see any mites or webbing or anything, so I figured it was probably dry (even though the soil was staying wetter than usual, if anything), watered it, and went on.

So by the time I noticed the actual spider mite infestation, it was too far gone to bother trying to save, which is how I learned the valuable lesson that even if it's subtle, a plant that appears to be going downhill is doing so for a reason, and you ignore the early signals at your own expense. If the leaves are not as glossy, if the stems droop a little more than usual, if the color's half a shade off, if the new growth is coming in a little twisted or discolored, there's something going on. Look into it.

(I also learned the lesson that I don't want to buy any more Hederas, though that one I had already kind of suspected.)

Still. H. canariensis is better than H. helix in a number of respects. They do, despite the fate of my own plant, resist spider mites better, and they also seem to be a little less hysterical if they get a little too dry or too wet. I still like them. I might even let myself get another at some point (as opposed to H. helix, which is strictly off the list, forever).

Hedera canariensis hanging basket.

As far as care information goes, well, I couldn't find any reference sources, so all I've got for you is my personal experience, the growers' guide (which is far more concerned about Hedera helix) and some educated guessing. Some skepticism is advised.1

Light: Indoors, bright indirect light seems to be ideal. My own plant, when I had it, also got some filtered sun once in a while. Solid green varieties might tolerate a bit less light, but I don't recommend it.
Water: Though the plant will tolerate a range of moisture levels, it's important to keep this fairly consistent, and never let the plant get completely dry or it will drop leaves. My six-inch pot seemed to be happiest when I watered as soon as it was dry an inch or two below the surface. It generally recovered from getting drier than that, but leaf tips would brown sometimes.
Humidity: The plant itself will tolerate dry air fairly well, but it has its limits, so don't ask it to handle central heating without a little help. More importantly, low humidity will give aid and comfort to the spider mites, if there are spider mites, and you do not want that.
Temperature: Generally not a consideration indoors; the species will survive temperatures down to 15ºF (-9ºC), though it will defoliate and/or discolor if it gets that cold (see Bunnies! Bunnies! It must be bunnies!2 for discoloration pictures). I couldn't find any guidelines for how low it can go before it discolors, but the growers' guide says not to go below 45ºF (7ºC), to maintain continuous growth, and I would be inclined to draw the line a little warmer than that, like maybe 50ºF (10ºC).
Propagation: One of the few really solidly excellent things about Hedera spp. is how easy they are to propagate. Tip cuttings, like one would use for a lot of plants, will work very well, but at work we've also propagated them, in the middle of winter, from single-leaf cuttings.3 For best results, keep cuttings in a warm, bright spot, with extra humidity if you've got it (e.g. a mini-greenhouse sort of arrangement would be helpful) and don't let them dry out: something should be visible within three or four weeks, if I'm remembering correctly.
Pests: Hedera species are very susceptible to spider mites, if slightly less so than H. helix.
Feeding: Hedera is somewhat sensitive to fertilizer build-up, so the growers' guide says to be sure to flush the soil often and avoid getting fertilizer directly on the leaves. Otherwise, feed as for any plant.
Grooming: Mostly limited to the removal of the occasional dead leaf. Vines that grow too long may be cut back; new growth will emerge from near the cut. It may help the plant's appearance to plant cuttings in the pot to keep the plant looking full, though I don't find this to be a huge issue with the plants at work, and when I tried to stick cuttings in with the parent plant at home, they usually didn't take; cuttings seem to need their own space. Plants can also be grown as climbers, though this seems not to be done indoors very often; not sure why.

Tangled mass of plants we grew from cuttings, as well as a couple Hedera helix that jumped into the shot at the last second.

There aren't as many cultivars of H. canariensis as there are of H. helix, but there still are quite a few. 'Gloire de Marengo,' the gray and white one pictured above, is one of the more common ones, and one also sees quite a bit of the plain green. We were offered a variety called 'Neon' at work, and bought some, and were extremely disappointed: the only special thing about 'Neon' is that new growth comes in bright yellow and then quickly turns green. I suppose this is slightly more interesting than a plant that's all-green, all the time, but not by much.4 As with H. helix, variegation patterns are said not to be incredibly stable, and sometimes plants will switch to other patterns, or revert to all-green (the latter is especially common if the plants are being grown without enough light), though I can't say I've seen this personally.

I suppose calling this one "Ghost" is a little bit of a stretch, though it does meet the one mandatory spook requirement, being dead. At least my own plant is. It also has one more ghosty thing going for it, which is that it haunts places: outdoors, it's got tendencies (like H. helix) toward being an invasive, noxious weed, and it's apparently difficult to eradicate from a given spot once it's become established there. The same easy propagatability that is so desirable indoors is a liability outdoors. As far as I could find, there are no major problems with this species yet, though it is reported to be invasive in small areas in California (the San Francisco Bay area, specifically), and it's on the noxious weeds lists for Oregon and Washington. Florida and Hawaii, who normally get all the good invasives, weren't mentioned in anything I looked at, which is very unusual: my intuition says that it's not that Hedera canariensis couldn't be invasive in those states, it's just that there are so many other invasive species there that it has a tough time building a base of operations. Though my intuition is not incredibly reliable.

They're also slightly hostile to the living, as ghosts sometimes are: like Hedera helix yet again, plants are poisonous, and in extremely good conditions, plants may flower and produce small, shiny black berries, which are also poisonous. Some people experience skin irritation after contact with the sap. I've never had any firsthand (or even secondhand) experience with this, but everybody says it so I figure it must be worth passing along.

So, all in all, how does it rate? Should you get one? Ennh. I don't consider it a plant that everybody needs to have, for sure. If you feel like you really need a plant that looks sort of like English ivy, this one is the best I've found so far: Hedera helix is a less attractive plant (in my opinion) even when healthy, and it's very often not healthy, and the only other option I have any personal experience with is Senecio macroglossus, which didn't blow me away with its great communication skills.5 Hedera canariensis is at least better than those two, I think.

-

Photo credits: all my own pictures, mostly not my own plants.

1 Really, some skepticism is always advised. Just, more so than usual in this case.
2 Oddly, "Bunnies! . . ." is one of my more popular posts, at least as assessed by the number of Picks it received at Blotanical. I know it isn't my best work, so I have to assume that the number of Picks is related to something other than the quality of the post. I just haven't been able to crack exactly what that critical something is, except to be fairly sure that there's a pro-outdoor-plant bias. Which is not surprising to me (anymore).
3 Which is to say, a piece of stem including a leaf and the node it's attached to: If the node is under the soil, the piece will root and sprout a new growing tip in about eight out of ten cases, even if you don't know what you're doing and aren't trying particularly hard.
4 (Though we did sell out of them, so I guess that's something. Considering how many very cool things we get in that nobody wants to buy -- er, nobody except me and WCW, that is -- I do have to grudgingly acknowledge that it's the Tradescantia zebrina, Codiaeum variegatum, Ficus elastica, Crassula ovata, Spathiphyllum spp. and Dracaena marginata that pay the bills. Hedera canariensis does, if nothing else, pay its own way. So I'll give it that much respect.)
5 Though I have to give it props for being a lot more pest-resistant. I never really got to the point where I could water it the way it wanted, but I didn't have bug problems.


11 comments:

sheila said...

I actually like this plant. I still have to watch for mites and deal with them sometimes, but way less than any other ivy.

In my interiorscaping job, we use it a fair amount as a filler in planters or for hanging baskets. It handles cool drafty places (like lobbies) quite well in the winter, whereas a pothos would go yellow and sulk in the same spot.

I took some cuttings from work that now live at home. In the summer, I use them in the window boxes on my porch, along with assorted annual flowers. In the fall, I bring them indoors and keep them in a cool place to keep the mites under control. I find that when the soil stays damp longer than expected, it is often the first sign that mites have moved in.

Periodically I take new cuttings when they get too long - the plants don't really branch when you cut them back.

All in all, a nice plant if you want that ivy look and can leap into action at the first sign of a mite.

I'll never grow any other ivy indoors. EVER.

Karen715 said...

I just wanted to let you know that the link to this post from your plant ratings list is broken. I kept getting an error message stating that it doesn't exist.

The post does come up using the search function, as well as in the post links for 6/29/08 to 7/3/08.

Yes, pity me. I have succumbed to the lure of the Hedera genus once again. ;-)

mr_subjunctive said...

Thanks for saying something. An extra pair of quotation marks got in there somewhere.

Anonymous said...

Just an FYI about H. canariensis hardiness. In Florida zone 9b it occasionally got minor frost damage to the newest growth. However where I now reside in Texas Zone 8b it froze to the soil line some years and died completely in the big freezes in '83 & '89.
My thought is they gotten it confused with H. colchica which is hardy to 6b and has leaves the
same size (or larger!).

rohrerbot said...

I know this post is older, but I had the same issue. I have tried growing this vine over and over again and now, I am officially giving up. I don't know what the deal was, but I always buy 3 of the same plant and try them in different spaces....in all three with different watering and sunlight schedules, they died. They do grow in Tucson as I see them all over...but I have been unsuccessful at trying to grow them.

Shawn said...

I found a small patch of this growing on campus here at the University of Georgia. I was surprised because I had only seen it growing outside in Los Angeles before. This part of Georgia is on the southern edge of zone 7b, but all the brick buildings and concrete on campus create a significant heat island effect, allowing some subtropical plants to live here.

Andreas B said...

Nice descriptions, but taxonomically it is a mess. Hedera canariensis has been split into several genetically distinct species. The cultivar 'Gloire de Marengo' belongs to Hedera algeriensis, the Algerian ivy (there is also a park called Marengo in Algiers). That lovely plant with the wine red stems and large five-lobed leaves actually is known as 'Spanish Canary'. It however doesn't belong to the species from the Canary Isles. It is at present classified under H. maroccana the Moroccan ivy. These plants are actually frost hardy and do well outside. The cultivar 'Neon' is a sport from 'Spanish Canary' and therefore should be typed: H. maroccana 'Neon'. There are several types of Hedera canariensis -the Canary ivy- that were collected from the wild. To my knowledge these are only cultivated in botanical collections, although they make great fast-growing plants with luxurious leaves.

Colin Purrington said...

In re: invasiveness there's a tendency for many people, even experts, to label all invasive Hedera as H. helix. E.g., all the H. atlantica in PNW. I suspect some of it is H. canariensis, partly because these plants filter from greenhouse/house to outside rather regularly. I'm sure it has invasive potential.

misspennyjean said...

Hello! I'm so glad I found this blog. I have a Hedera Ivy that I've been growing for about 8 months or so. I'm not sure exactly what type it is, the tag just said HEREDA, but I think Helix or maybe Canary Island or even perhaps Pitsburgh. I'm really confused and lost with the amount of googling I've been doing, so PLEAAAAAAAAAAASE...

I hope you can help me!


I'm super worried about my Ivy right now - I live in South West W.A. Australia and my Ivy is having her first winter (avg temps between 6°C and 17°C) - I thought I should bring it inside (it was pouring with rain and crazy winds) and I hung it up in the bathroom to drip dry.

A day or so later, for some UNKNOWN AND STUPID REASON I hung it inside a vacant room and shut the door. My plant then stayed inside that dark, cold closed off room for about a week or so. This is when I panicked: the leaves went from a nice dark green to a weird muddy brown sort of yellowish colour.

1. https://i.imgur.com/Rfr9eid.jpg (The ivy plant in question. It now sits in the laundry opposite a west facing window. I am concerned with the discoloured leaves.)

2. https://i.imgur.com/EBTuR81.jpg (Ivy again with flash)

3. https://i.imgur.com/V3gjRMD.jpg (Close up of some of the leaves, noticed that a couple have brown splotches)


Is this colouring because I've moved it and had it in the dark for so long? I have been researching Spider Mites and I'm really worried that this is the end for my plant :(

PLEASE HELP! Thank you so much for blogging :)

Penny

mr_subjunctive said...

misspennyjean:

It's a Hedera helix; I won't try to guess the cultivar. I haven't tried to grow H. helix in a very long time, and it didn't last long then, so I'm not the ideal person to advise you, but I'll take a stab at it anyway:

Doesn't look like spider mites to me. If it is, you'll know very soon because you'll see webbing.

My guess is that the plant had been in a bright spot where it was actively growing and transpiring water from the soil, drying out relatively quickly, and then you brought it into a dark spot where it couldn't actively grow and wasn't pulling water from the soil, so it's wet, and that's why the yellowing. Give it a bright spot without direct sun, ideally with humid air, and check it every day or two to see whether it needs water until you get a feel for how often it needs to be watered now that it's inside.

Even if you did everything perfectly for the plant when you brought it in, I would expect some leaf drop, just because the conditions have changed so drastically for the plant that it has to adjust to the new situation: leaves adapted to function outdoors might not be worth the energy to maintain indoors. (Disclaimer: some plants do this much more than others; I'm not sure Hedera is one of the big leaf-droppers.)

As with all plant-mistreatment issues, there's no way to go back in time and do things differently, so you'll just have to give your plant the care it likes and hope that it can pull itself together. Often they can, so don't panic.

misspennyjean said...

@mr_subjunctive

I wanted to say thank you for replying to my question so quickly! So kind of you, you've really put me at ease.

Also sincE I posted my last comment I have done some extensive reading on everything Hedera and would just like to point out one missing factor from my story: This is also MY first winter!
I've moved here within the last 12 months and for 30-odd years before that I lived in Darwin NT, AKA The TROPICS, 32C hot humid and sunny 365 days a year hahaha. So, I guess this is the first time dealing with such drastic changes in environment as well! Also, I knew I was lax on controlling the humidity, but now i can add a future note to self: PEST CONTROL.


And yeaaaaah I already did the whole rinse the ivy leaves in the shower thing for possible spider mites, but didn't do a thorough leaf check or anything drastic. I've placed the cursed thing outside under a big bushy tree on a broken old chair where it can stay. For now. Until I decide if I want to keep it or not after reading so much into it. I don't want to deal with the potential for spider mites right now, thank you :)