Saturday, October 6, 2007

Rhubarb Rheum rhabarbarum

I am an amateur naturalist trying to learn something about everything living in my garden.

Situated in my garden border (at (0.6,1.0) - see here) is a patch of rhubarb I grew from seed some years ago. Frustratingly for the purposes of this blog, I have since lost the seed packet and can't remember the exact variety - there are dozens - though it may be Hawkes Champagne (is anyone out there expert enough to tell me from the photo's alone?).

Photo 2, which I took back at the start of May, shows a closeup of my rhubarb's flower stalk. For some reason I'd expected the flowers to smell unpleasant, but in fact they give off a sweet, heavy perfume and are very popular with pollinating insects.

Photo 3 shows the same flower heads some weeks after photo 2 was taken, now 'dripping' with red seed capsules.

I enjoy my rhubarb mainly for its architectural value in the flower bed, though I do occasionally cook some of the stalks. As everyone knows, rhubarb leaves are poisonous. They contain quantities of nasty chemical oxalates and (laxative) anthraquinone glycosides, and although (as I read here) you might need to eat a few kilogrammes to seriously risk death, eating far less would be enough to bring on some pretty unpleasant consequences.

By now, in my quest to discovery something about everything in my garden, I've learnt to expect everything I come across will have a long and remarkable history. Rhubarb certainly lives up to expectations! This site has answers to every rhubarb-related question I could imagine asking (and some I couldn't) and amongst other things I learn that rhubarb gets mentioned in Chinese herbals from 2700BC; that a general in the Ming Dynasty tried to commit suicide by overdosing on rhubarb medicine; and that the famous Marco Polo writes at length on rhubarb in his accounts of his travels. Rhubarb was being grown in Banbury, Oxfordshire (about 15miles from my house) "by Hayward" in 1777 for its herbal value. According to this site, the first English culinary recipe appeared in 1783 in John Farley's book 'The London Art of Cookery', and from the site of the Royal Horticultural Society I learn that in its heyday in the Victorian era, Yorkshire in the North of England was producing 5,000 tons annually. Rhubarb was imported into Maine in the US in the 1790's.

The UK's national collection is today held in the gardens at Harlow Carr. Now, I have nothing but respect for the botanical value of such collections, but I have to confess that the schoolboy in me can't restrain a titter when I bring to mind Python-esque phrases such as "The nation's rhubarb heritage".

Botanically, rhubarb is a member of the polygonaceae family of plants, comprising about a thousand species including sorrel and knotgrass.

Returning to the subject of my rhubarb's flowers, photo 4 shows a close up of a single flower (40x magnification). Rhubarb flowers have nine tiny white petals. In the centre of photo 4 you can see the threefold 'feathery' stigma, which sits atop the pistil - the female part of the plant. A grooved, waxy pollen-containing anther - part of the plant's male 'apparatus' - can be seen bottom, right-of-centre. Photo 5 is my photo of some rhubarb pollen. This site gives a detailed botanical description of the polygonaceae and contains a link to labelled botanical drawings of rhubarb flowers.

And finally, in preparing for this posting I was delighted to discover that Ulm, Montana hosts a rhubarb festival . My imagination runs wild! If you're reading this and have attended, please leave a comment to let me just what it is that goes on at a festival of rhubarb!


Anonymous said...

I have only one rhubarb in my garden,
nothing about it, but those moles !
I have to say, that none moles in our town garden. The reason for that is our Golden retriever, who is a real mole dog. He is waiting very patiently near just a right hole and
catching moles quickly as lightning.
I can recommend a dog like she is :))

Thanks for your comment on my blog.
You have here an interesting blog ( I am a biologist ;) ) said...

Rhubarb Pie....Yummmm