Tuesday, 15 September 2015

The double-r, double-n, double-flowered Sparrmannia


We have quite a few of these double-flowered cultivars of Sparrmannia africana in the Royal Botanic Gardens Victoria. 'Flore Pleno', as it's called, suckers readily and tends to form clumps 3-4 metres high and across. The single-flowered form is, to my mind, far prettier but all of ours in flower at the moment are doing this fluffy thing.

In our database the species is listed as a member of the lime tree family, Tiliaceae, consistent with some of its Common names in Europe: German Linden, House Lime or Indoor Linden (although the latter name is sometimes applied to another species, Sparrmannia ricinocarpa). More recently this family has been combined with others into an expanded mallow family, Malvaceae.


The leaf looks a bit like a Tilia (lime or linden), the soft stems make you think of a Hibiscus (mallow) and the hairiness is a bit like a Brachychiton (in the Sterculiaceae, now also part of the Malvaceae). So I'm not too fussed either way.

As the species name and another common name African Hemp suggest, this perky shrub is from Africa. It is also know as Cape Stock Rose and Cape Hollyhock in honour of its natural habitat, in damp forest margins and hillsides around the Cape of Good Hope. The whole genus in fact is only found in Africa and Madagascar, and contains between three and seven species (its taxonomy and nomenclature seems a little uncertain).

Alice Notten, from Kirstenbosch National Botanical Garden in Cape Town, provides some excellent background to this species and its nomenclature on the South African National Biodiversity Institute’s PlantZAfrica site. In the single-flowers (prettier) form the flowers have a brush of red and yellow stamens (male parts with pollen) protruding from the white petals. As Notten says 'much of the attraction of this flower is in the puff of brightly bicoloured stamens'.

These stamens are sensitive to touch and 'puff out' when a visiting insect bumps against them, spraying it with pollen. But it gets better. Another way the plant encourages insect visits, and therefore potential pollination, is to offer up sacrificial stamens, with knobs, to be eaten.You can see them in this gorgeous image taken by Stewart R. Hinsley and reproduced from the Malvaceae pages.


You sometimes see the name Sparrmannia spelt with one less 'r'. This is because in the original description, by the son of Carl Linnaeus ('Carl Linnaeus the younger' or 'L.f.'), the name was rendered incorrectly. It took over two centuries for this to be fixed but he name has now been 'conserved' with the correct spelling as this was clearly little Carl's intention (he actually spelt it correctly when he got to listing the species). 

Anders Sparrmann was a Swedish surgeon and botanist, travelling with James Cook on his second world voyage and then later collecting around the Cape. He introduced Sparrmannia africana into cultivation in Europe in the late eighteenth century, where it became a popular glasshouse plant (the Indoor Linden...).

That cover most of the names you'll see used for this species. As to African Hemp, fibre has been extracted from this plant but of low quality. And flore pleno is Latin for 'full flower' and is used in horticulture for double-flowered forms (although I wonder if this particular cultivar has more than one extra later of petals - I'm assuming that every stamen has been replaced by a petal, as we saw in the hellebores.

Plenty of flower, and flowers, to enjoy and plenty of time to do it. In South Africa it can bloom from mid-winter to early summer. My pictures were taken at the start of the flowering season, in early July (with all plants yellowing a little), and it is still floriferous now.


4 comments:

Dave Bright said...

Hi Tim
That's a beautiful photo of the single-flowered form - and,like you, I prefer it to the rather 'blowsy' flowers of the double!
I'm fascinated by the etymology of names - have you ever blogged about Lechenaultia/Leschenaultia?
Regards Dave

Tim Entwisle said...

Thanks Dave. Such as shame we don't have the single form here, and that I couldn't photograph myself! I get a little side tracked on etymology occasionally so glad to hear at least some readers enjoy this. No haven't done Le(s)chenaultia but will add it to my list...
Best wishes, Tim

Stuart Read said...

thanks Tim - I'd thought this was Dombeya natalensis/cymosa - but checking, that seems only single - so thanks for the elucidation. The latter smell good - almonds or such. What about Sparrmannia? I think not? Quite a few old Sydney gardens have Dombeya/Sparrmannia in them, still, despite the ravages of time and anti-shrubbery fashions. cheers, Stuart.

Tim Entwisle said...

Ah, yes. My first thought was also Dombeya. Took a bit of tracking down but interesting plant and a nice old fashioned one at that. Tim