Sempervivum arachnoidum is a species of Sempervivum that has webbing. You can use this thread to post your pics of this family of plants. Note that the arachs have been heavily hybridized. Another interesting tidbit is that the arachs can be very small. Some of the smaller semps we have are arach hybrids.

Below is a pic of S. arach. 'Silver Crows' showing the dense webbing covering the growing crown of this plant.

That is a lovely semp twit. I love it's open habit with such wonderful webbing in the center.
Here is my S. arach 'Cebanese'. I lost almost all of them this last fall and winter to drowning. Not their fault, just didn't realize they needed to be moved. I feel sad that I was so remiss.


This poem was found by ridesredmule (Charleen), thank you so much Charleen.

This poem was printed in Gardening Illustrated about 80 years ago. I don't know who wrote it but Ingwersen quoted it in an article on Sempervivums in 1943.

THE COBWEB HOUSE LEEK

Of alpine flowers that grow so neat
The Houseleeks are the most complete
Of all the Houseleeks neatest far
The jolly Cobweb Houseleeks are.

They're always hearty, always hale,
The will grow in the merest shale,
Thrive in the country, do well in town
Grow happily forward, never look down.

They never sulk, they never die.
They smile at every kind of sky,
They grow on walls, on roofs they revel
And will do well upon the level.

Tectorum's always on the roof.
But Wulfenii is more aloof.
Comillii is purplish blue,
And rubicundum smiles at you.

But triste is not really sad,
To name it so is wrong and bad.
Calcareum so cosy and round
Does many and many a bed surround.

Yet why compare? All Houseleeks known
Possess a charm that's quite their own.
But Cobweb Houseleeks, every way
They are the perfect picture, they.

I just can't seem to keep Cebenese alive. I think it was too much moisture during the winter like you. I also ran into an arach called 'Cobweb Buttons'. I lost most of those shortly after getting them, but managed to save two small chicks. I never water them and they are doing fine, if small. So I guess some of the arachs out there can be very fussy about water.

I have 'Cobweb Buttons' also, it is a new plant to me this year. Hope I can keep it alive through this winter. And another new one is S. arach 'Stansfieldii'.
S. arach 'Cobweb Buttons' and S. arach 'Stansfieldii'

I think what I will do is take a few offsets from them and try them in different situations. All with good drainage.

Lynn, those are good pics, but can you edit your post to attach labels to them, so there is no confusion regarding ID?

Thank you twit. I didn't think about it being confusing on which was which. Good thing you are watching out for all of us. Much appreciated.
I will have to go through my semps and see if I have any other arachs. I really love those spidery little guys.

I thought that's what the order was, but not sure.

Here's one of the hybrids. It's S. arach. x pittonii, a real beauty. It is a hybrid between the two species that is medium sized and never gives me any trouble. Doesn't seem to care about how much it gets watered or how cold it gets. It gradually fills the space you give it, then plays nicely with its siblings to produce a wonderful ground cover effect as you can see here.

That is truly lovely twit.
Here is a new hybrid for me this summer. Not sure what it will look like when the rosettes open. Hope it shows some webbing.
S. arach x montanum 'Hausmanii'

Well, I'm a bit puzzled now. I thought that S. hausmanii was a species of sempervivum, but the name you used suggests not. I guess we need to do some research. I do really like my hausmanii, as it is very nice and easy too.

I'm afraid I am as puzzled as you are. The tag shows it as S. arach x montanum 'Hausmanii'. I will see if I can find more info on it. Maybe I should just show it as S. arach x montanum Hausmanii? I am finding it with a up case H.

My tag was just S. hausmanii. So the questions become: 1) Is there a S. montanum 'Hausmanii' or perhaps S. montanum f/Hausmanii? 2) Is there a S. hausmanii? 3) Is "Hausmanii" or hausmanii a name for a hybrid of arach and montanum? 4) Is your plant a hybrid from Hausmanii of arach and montanum?

I think I'm getting a headache. It hard to be accurate. I'm so confused!

I believe it is a hybrid of hausmanii and montanum. Let me go out and get a photo of the tag.

I love all the arachnoideums. Lynn, I like the shape of 'Cabenese' - looks like they came back well. Twit, S. arach. x pittonii really is a beauty. Such a soft color.

Wish that photo of 'Cebanese' was from this year Chris, but it's not. It's from last year. I just have a few singles that survived the wet winter and spring we had here.
Twit, here is a photo of the tag that came with the above hybrid hausmanii. What do you make of it?

Lynn, I believed you without the pic. Been trying to find out more information, but not getting very far (watching my bandwidth again!)

I just put the pic to see if you think maybe it should have been hausmanii instead of 'Hausmanii'?
Boy this can get confusing.

All it takes is one typo, and it's confusing from then on...

Jacki I find S. arach x montanum 'Hausmanii' both ways in a google search, so have it in my database as per what the tag says that came with the plant. Not sure what to do from there.
I will try to find out more about it.
Here is S. arach 'Ali'

I got Ali in a trade earlier this year. I thought I was going to have a rot problem with it as a couple of the tiny chicks in the trade rotted. But the rest hung in there an are doing great. It looks like its a smaller semp to me, but its too soon to tell yet.