Dioscorea Elephantipes in the Arctic

[NeillieB]

Hello all: my first post.

Last May, I inherited a gigantic elephant's foot from my mother's garden in Cape Town (well, gigantic for me – I've seen bigger, but he's about the size of bowling ball, I suppose).

I took it back to arctic Norway, where I now live, from the southern hemisphere winter to summer. I live a few hundred kilometres north of the arctic circle.

And, well, I have a few questions!

When I got him home, he was active, with a nice big vine. But he's still dormant. I understand it's not out of the ordinary for plants that make this journey to miss a season. Is that right? (I'm not too worried about the continued dormancy, although this is unusually long).

Secondly, does anyone know if it's going to be all right in the polar day? We have just under three months of midnight sun here. I wonder if that's going to be all right. Should I take any special care to darken the room? I'm assuming that light, as much as water and temperature, help to decide cycles, and I don't want to stress it.

Thirdly, some of the 'scales' have fallen off, revealing a lighter, rough patch underneath. I've never seen this before. The skin underneath is rough and hard. I have a suspicion it's growing in this spot quicker than it is elsewhere. But again, it can't be a coincidence that this happened after I got it home. Could this be damage?

I have some questions about encouraging roots, too – it seems to be a bit loose in the soil. I've ordered some rooting gel, and I'm wondering if anyone has any elephantipes (or caudex) specific tips?

A long first post! I have a suspicion this is the right place.

[iann]

These have a mind of their own even in normal conditions. Moving from one hemisphere to the other seems almost guaranteed to cause confusion.

Does sound like there is some damage though, not normal for bits to flake off. Or maybe it is normal when they become huge?

[NeillieB]

Thanks Iann.

Yes... confusion seems inevitable.

My suspicion is that I've simply been overwatering it and it's simply swollen faster than the bark can accommodate...

[NeillieB]

Does anyone have any thoughts on whether a few weeks of midnight sun will be a problem for caudiciforms?

I'll post pictures of my whoppers as enticement...

[Tina]

Hi Nellie
My two plants lost some of there 'nodules', it was after a repot and I think it was a growth spurt as they had been neglected previously, they lost some of the rugged appearance but seems fine.

[NeillieB]

Tina, thanks so much for that. A relief to see photographic evidence!

Yes, a growth spurt's my diagnosis too. It was a very dry summer in the Western Cape and I was watering fairly parched plants... that would make sense..!

[Terry S.]

I am not a big grower of caudiciforms but the majority are summer-growing with a dormant tuber sitting below ground through the winter. I would imagine that such plants would be no problem under your conditions. The only caveat is that we probably have no information as to whether any of these plants use the CAM mechanism for photosynthesis. If they do, then darkness is required for them to open their stomata and absorb carbon dioxide. My guess would be that those with non-succulent foliage would not use CAM.

However, my experience of four plants of D. elephantipes is that although they start into growth any time from July - September (UK), they are essentially winter-growing with the vine sitting on the plant and nourishing it through winter. So I suspect that these would be tricky under your conditions without auxiliary lighting.

[NeillieB]

Thanks Terry. Yes, auxiliary lighting in winter is absolutely required, for sure. The sun doesn't rise between November and January up here, of course, which is problematic for basically everything that isn't adapted to twilight and sitting out the snow.

D. elephantipes are winter-growing plants in situ, of course... but mine do what they like, anyway! My two smaller ones have been in vine for some eight months now, so they'll probably be dormant for the midnight sun, thankfully. The big one's just sitting there, and by rights should be getting going any minute... I was just a little concerned that I might be stressing summer-dormant plants with all that continuous sun...

[NeillieB]

Just as an update – he's back. The old chap's sprouting.

So, conclusively – your elephantipes can lose scales and prosper. It was pretty clearly a growth spurt, probably on a plant that I watered too much after a dry, hot summer.

[Chez2]

Watching this thread with interest. I bought my hubby one for Christmas. I realise we are talking about a different location.