Woolly Cobweb Houseleek: Sempervivum arachnoideum ‘Clärchen’

Sempervivum arachnoideum 'Clärchen' has pink flowers and cobweb rosettes

You don’t need me to tell you how the cobweb houseleek (hen-and-chicks, or in botanical terms, Sempervivum arachnoideum subsp. tomentosum) got its folk name. Those with a fear or spiders or a compulsion to dust might find this plant unsettling. If it looks on the creepy side, try to imagine the leaves are playing cat’s cradle.

Delicate webbing covers each chick from infancy, stretching out as the evergreen rosette swells to maturity.

Sempervivums look to the next generation, producing lots of tiny offsets. When the pink, star shaped flowers eventually appear, they have male and female parts as an insurance policy. Once a rosette has produced a flowering stem it will die, leaving the multitude of pups to fill out its place.

The plant will sulk if its feet are allowed to stay wet, requiring a sunny spot and good drainage. Given that, you can pretty much ignore them to your heart’s content. Traditionally grown on rock walls, gravel gardens and roofs, sempervivums were believed to offer protection to those who grew them.

The plant’s original cultivar name is ‘Clärchen’. This flowering specimen was labelled Sempervivum arachnoideum ‘Clairchen’ in RHS Harlow Carr’s glasshouse. Online, I also found ‘Clarchen’ and ‘Claerchen’. Take your pick!

Shared for Cee’s Flower of the Day.

31 Replies to “Woolly Cobweb Houseleek: Sempervivum arachnoideum ‘Clärchen’”

  1. “Arachnoideum” got me. The thought of an arachnoideum that is sempervivium gives me the willies. But there’s no denying the glory of those blooms or the intricacies of the plant. A worthy Flower of the Day and a beautiful photo!

    1. My sweetheart is scared of spiders and my mother loves them. I’m in-between, though I do tend to panic if I see one scooting towards my sweetheart…. for very good reason!

      I wonder if these are more or less hospitable to spiders than the other ones.

      1. I take a live-and-let-live approach to spiders outdoors, but indoors? Not so much. Seems to me it would be hard even for an accomplished spider to spin a web in that sempervivium. What knots would ensue! I feel a giggle coming on.

        1. Good point. It might be like painting over a very similar colour – you start to lose your grip on which bits have been done and which still need doing.

    1. I have an ordinary, hairless one on my windowsill and it really is very easy. It was just a single rosette when we won it (it was a door prize). I didn’t want it at the time, but have become fond of it. Now it is overflowing both sides of its pot even after some was repotted in a second pot.

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