Saturday, March 1, 2014


It's thanks to the bee's and the chance find and intrigue of a plantsman. Its pedigree may never be really known, but my what a beautiful exotic looking flower that originated from England no less. Named after the nursery where the plant originated and is  still sold today at the Holden Clough Nursery, Bolton-by-Bowland, in Lancashire. Considered to be a 'Water or Bog Iris' but so long as you take care not to let the plant dry out in the summer season until the plant is established it will grow well in the regular garden, and I find it does appreciate a bit of midday dappled shade.

The Iris Yearbook (BIS), 1971, Holden Clough - An Unusual Iris Hybrid. Donald M. Patton.
Walking around a nursery in Yorkshire we noticed a short row of Iris whose foliage was unfamiliar but although it was not yet in Bloom and the staff of the nursery, in the absence of the proprietor, could give no information about it, a plant was purchased and taken home. When early in June the first flower opened it was seen to be one that did not match any known species or hybrid. There was however, some resemblance to I. pseudacorus. On making further enquiries at the nursery it was established that the plant was an odd one out of a batch of seedlings raised from a pod of seed taken from a plant of I.chrysographes. All the other seedlings appear to be similar to I.chrysographes.
A plant was given to Dr Jack Ellis who made a chromosome count and found that 2n=37. If we accept that the plant came from I.chrysographes seed then since the chromosome number of that species is 40 that of the other parent must be 34 and this fits I. pseudacorus. It appears that I. pseudacorus was not actually growing the nursery where the hybrid originated but it has been known to grow wild nearby and it is not unlikely that bees carried the pollen to the nursery. Pending closer examination of the chromosomes, therefore we feel satisfied that the hybrid is I.chrysographes X I. pseudacorus although this is a cross not previously recorded.
Apart from its botanical interest the new hybrid is quite an attractive garden plant with a very unusual flower colour. It is, therefore been registered under the name of 'Holden Clough' to commemorate the nursery where it originated and the plants will be obtainable from the nursery of Mr Linnegar.
The plant is less vigourous than I. pseudacorus but has many similarities including the leaves which have a distinct rib and are about 24 inches high. The flower is yellow, closely veined purple and the general effect is brown. The falls are flaring and have a bright yellow spot pattern created by a deepening of the veining around the spot area. The standards are small and stand at an angle of 45°. The style arms are cream and the crests purple edged yellow. The stems are well branched and carry the flowers to a height of 26 inches. Like pseudacorus the rhizomes are hard and red fleshed. The roots are strong and the plant appears happy in a damp spot. It seems to be an excellent grower and very free flowering. Dr Ellis reports that the pollen is sterile but the seed pods persist on the flower stems and there appear to be a few seeds although we do not expect that they are viable. The seed pod is triangular, dark green and not unlike that of I. pseudacorus.

Bulletin of the American Iris Society, Summer 1978, Number 230.

At the Species Level ; Those Wide-Cross Hybrids-Hooray!
In scanning lists of wide crosses and presumed hybrids raised in the past, a species that frequently appears is I. pseudacorus. Although we have no proof that some of the old reports were of authentic hybrids (and plants are no longer around for chromosome study), there can be little doubt now that this species is an important tool to future apogon iris breeding. In Japan, after generations of attempts, have been produced yellow Hana-shobu hybrids yellow Japanese irises-while in Britain the brown water-flag HOLDEN CLOUGH is thought to have been sired by I. pseudacorus on I. chrysographes (one of the Himalayan Sibiricae).

The Iris Yearbook (BIS), 1978,The Hugh Miller Trophy
This trophy restricted to non-bearded irises, was awarded in 1978 to the inter-species hybrid 'Holden Clough' selected and Registered in 1971 by the late Donald Patton. The flowers are yellow, marked purple, giving a brownish effect. It was found in a nursery in a row of seedlings from I.chrysographes and the pollen parent is believed to be I. pseudacorus. It was given an A.M. by the Joint Iris Committee in 1973, and the the B.I.S. in 1976.

 Bulletin of the American Iris Society, Fall 1978, Number 231.
A Shiny Yellow Seed on 'Holden Clough', Roy Davidson, Washington.
In my work with iris species I have followed not only the species themselves as new and better forms were found and introduced, but also the hybrids, those not conforming to anyone species, no matter where they originated. Thus I was most intrigued with the idea of a brown water iris when I read in the British Iris Society YEAR BOOK 1971 of Mr. Patton's finding it in a nursery row of supposed Iris chrysographes. Later it was proposed that somehow pollen of I. pseudacorus had been responsible for those aberrant plants in the row. Dr. Ellis made a chromosome Count, reported that the chromosome component would allow that premise, and it went on the record that the plants were hybrids of I. chrysographes and pseudacorus. There were, however, some discrepancies to that theory. For example, how could two such thin-leaved, deciduous species have
given rise to a hybrid having firm, rigid leaves that would stand up to considerable freezing?
Melrose Gardens had imported this hybrid HOLDEN CLOUGH into California, and a piece was planted in my Washington state garden in autumn of 1976; most surprisingly it flowered the following spring, although in my absence. The stalk was there, however, on my return, and it stood up firmly through the winter in a manner that no I. pseudacorus nor any other water-loving species can maintain.
It has been Ben Hager's idea that somehow I. virginica was possibly responsible for HOLDEN CLOUGH, mainly as an explanation of the firmly evergreen foliage. However, the stalk of that species is among the softest of all, often collapsing in a mush before the capsules are open.
This last iris season saw another stalk on my HOLDEN CLOUGH plant which by then had increased to three. The stalk reached twenty-eight inches high, and a total of ten flowers were given in a long season of bloom, the flowers held just above the foliage which had elongated to thirty inches. In full sun the leaves had a good rich green color, further enhanced by a nice polish to the surface.
Just across the path from HOLDEN CLOUGH grows a well established clump of I. foetidissima which was on the property when I came. I was struck by the similarity of the two plants, and although I did not have flowers simultaneously for comparison they seem, in memory, to have been decidedly alike except for color. In the process of comparing the two I had cut the stalk of HOLDEN CLOUGH, and a few days later Phil Edinger discovered that one of the shrivelling pods had an unmistakably hard, round seed in it. Right away the stalk was put into a bottle of water, where it stood for a week. Finally the strain of waiting became too great (and it was evident anyway that the entire stalk was beginning to dry up) so the seed was removed.
In two ways it was a very curious seed. First, it had a distinctly shiny yellow seed coat, and that had been hoped for since it would give almost certain evidence that HOLDEN CLOUGH had been a chance development from I. foetidissima. A pod of I. foetidissima, opened for comparison, revealed that at the same approximate stage of development its seeds were about the same appearance and color, though they would redden up later. The second odd detail of this seed was its shape: rather than round and bead like, it was sort of bi-lobed, almost as though two ovules had become fused (or had not become fully separated? Ed.). This seed is of course planted, and with high hopes; except for shape it was quite plump and normal appearing. What can we hope for, beyond germination and growth? Should it in time produce flowers, will they reveal the answer to the parent's ancestry? The label in the pot reads simply HOLDEN CLOUGH F 2" • • • Editor's note: The chromosome count of HOLDEN CLOUGH made by Dr. Ellis established the possibility that the parents could have been 40-chromosome I. chrysographes and 34-chromosome I. pseudacorus. Interestingly, 40 chromosomes also is the count for I foetidissima.

Melrose Gardens, Stockton, California. The Connoisseurs Catalog 1981
Water Iris.
HOLDEN CLOUGH Unusual hybrid between iris pseudacorus X ?. Rampant, evergreen plants produce tall, branched stems and smallish flowers gold ground veined brown maroon...........................................$4.00

Tempo Two, Pearcedale, Victoria, Australia. Iris, Daylilies, Hosta Catalogue  1994-1995
Iris Species suitable for water or boggy conditions.
Chrysographes hybrid, maybe I. pseudacorus X ? Flower are an intriguing brown with deeper veining. Not showy but of interest for floral art and will grow in water conditions as well as normal beds..................................... $6.00

IRISES, A Gardener's Encyclopedia, Claire Austin.
HOLDEN CLOUGH D. Patton, , R. 1971. Change of classification and description to: Wide apogon hybrid of unknown origin and totally unlike I. chrysographes with which it was found growing. Resembles both I. pseudacorus and I. foetidissima and in many respects seems intermediate between the two. Evergreen foliage in warmer climates. Occasionally sets seed with colored flesh outer seedcoat. Flesh of rhizome is pinkish as in I. pseudacorus. Chromosome count 2n=37 made by Ellis; Previous checklist entry below.

The Garden, June 2013. Roy Lancaster visits... Holden Clough Nursery.
'Named after the nursery'.
A plant in cultivation that originated from this nursery in the days of Richard Milne-Redhead is Iris Holden Clough which has been considered by some to be a curious form of the British  native flag ( I.pseudacorus) differing in the purplish brown heavy veining of its yellow flowers. To my eye at least, this gives them a somewhat muddy appearance from a distance. John's (Foley) description of it as a 'Marmite plant' (you either love it or hate it) is most apt. It is definitely a plant for collectors with its curious flowers and winter green leaves. It is also versatile in its growing requirements coping with both moist and average garden soils.

AIS Checklist 1979
HOLDEN CLOUGH    (D. Patton, R. 1971).  Chrysographes hybrid 26" (66 cm) L.     Yellow, veined purple, giving a rich brown appearance; form resembles I. pseudacorus. I. chrysographes X I. pseudacorus., S. Linnegar 1971.

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