Monday 3 December 2007

Wot! no rhizomes?

All botanical descriptions of the Canna genus contain a reference, such as the following one quoted from the Wikipedia,
"The plants are large tropical and subtropical perennial herbs with a rhizomatous rootstock."

Please note the reference to rhizomes. One hundred and fifty years ago, Canna musaefolia was recognised as a Canna species. It was described by Monsieur E. Chaté, the author of the worlds first book devoted to Cannas, in the following manner.

"This species was formerly described in the English, Dutch, and German horticultural journals under the name of C. excelsa. It was named C. musæfolia by Monsieur Théodore Année, who introduced it into France in 1858, from the resemblance of its leaves to those of the Musa or banana-tree. It reaches a height of more than 8 ft. and has green, downy stems, and very large, oval, green leaves. Flowers small, orange-yellow. It is a tender species without rhizomes, and requires to be kept constantly growing. Peru."

The point of the quote being that there were no rhizomes. Canna excelsa (and by implication C. muaefolia) is accepted as a synonym of C. paniculata. However, all known Cannas have rhizomes or tubers. So, you can imagine our surprise when potting up a C. paniculata, started from seed this year, to discover that it was totally without rhizomes. I first thought this was some sort of freak, perhaps caused by the extreme weather we have *enjoyed* this year. The seed came from a reliable source, originating in Peru.

We now hear from Dale McDonnel in her excellent article The effects of drought on Cannas, 19 November 2007 on this blog, that she is also the custodian of such a Canna freak. Dale obtained her specimen from the old Bendigo Canna Collection. It long ago lost its identity and is either another of the very early French hybrids or a species Canna. Dale nicknamed it "The Bendigo Banana" because of its close resemblance to a Musa. It has never flowered for her and cannot be identified until it does. The foliage is a pale, lettuce green, poised on long, arching pedicels. The long leaves, have prominent, close veins, undulate margins and fold downwards. In windy weather these split and look just like Musa foliage. It does not tiller like other cannas. Each leaf stalk arises from an individual small conical knob.

In his book, Le Canna, Monsieur Chaté also described two hybrids that Monsieur Année had raised, based on C. musaefolia. The first was C. 'Musaefolia Minima' , which he described as
"Leaves of a whitish green, badly set. Flowers small, orange brown. No rootstocks. Introduced by Théodore Année, Passy, France, EU in 1860."

The second was C. 'Musaefolia Perfecta', which he described in the following terms
"Stems from 5 ft. to 6½ ft. high. Leaves broad, very firm, of a handsomish whiteish green. Flowers small, yellow. Roots fiberous, without rootstocks. Introduced by Théodore Année, Passy, France, EU in 1862."

It is too early to draw any conclusions, but it would appear that Dale has a specimen which is either the original species, or one of the two hybrids. Until it flowers, we will not know. All three possibilities have different flowers, so it should be possible to put a name to it then. In the meantime we are trying to keep our specimen alive and growing over the winter.

Based on Monsieur Chaté's descriptions we can speculate that what many gardeners call Canna 'Musaefolia' is, in fact, one of the five hybrids raised by Monsieur Année. Two of them are described above and have no rhizomes, so that leaves three known possibilities, C. 'Musaefolia Hybrida', C. 'Musaefolia Peruviana' or C. 'Musaefolia Rubra'. They may, of course, be an example of C. 'Musaefolia Grande', introduced by Herb Kelly from Venezuela in 1989.

Finally, we must not forget that there may have been subsequent cultivars raised in the interim period since Monsieur Chaté authored his classical canna book in 1867, however, all focus was switched to the floriferous Crozy Group from that time onwards. We have been lucky enough to acquire the three separate Musaefolia cultivars with rhizomes, all named. They were not spelled correctly, but hey, after 150 years that is not a big deal.

3 comments:

  1. Glad to report that the "Bendigo Banana" referenced above, has finally flowered. I've been waiting for five years to see it.

    The exceptionally mild winter we experienced allowed it to keep chugging away over that period instead of succumbing to our usual light frosts. Normally it would be manually cut to the ground in early winter, but illness prevented me from trimming anything these past months.

    I almost missed the flowers as I did not expect anything from it so early in our growing season. It has a tiny orange-red flower which appears to be identical with Canna tuerckheimii.

    The plant's habit and leaf shape also closely resembles Canna tuerckheimii, - foliage may be a bit more on the pale lettuce green side than pics I've seen of this species growing in the wild.

    The lack of rhizomes on my plant throws an element of doubt into my mind about a definitive ID, as I have never seen reference to this characteristic for C.tuerckheimii. Could it be a geographical variation for that species?

    It would be interesting to obtain some seed from true tuerckheimii and compare my old Bendigo Banana with it under the same growing conditions.

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  2. Dale,

    That is great news. Are you sure that it is not C. 'Musaefolia Minima' , which Chaté described as

    "Leaves of a whitish green, badly set. Flowers small, orange brown. No rootstocks. Introduced by Théodore Année, Passy, France, EU in 1860."

    Malcolm

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  3. Don't think so Malcolm. No way you could describe the flowers as orange-brown, no matter how fanciful you were. I presume that by "whitish green" he was referring to a waxey bloom on the leaves. No hint of wax on this Canna.

    I'll post a very bad pic taken on a windy day. By the following day the flowers were history.

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