Journal of the Royal
Horticultural Society, N.S. 21: 205-212 (1897)
CROSS-FERTILISATION OF FLORISTS' FLOWERS
By Mr. JAMES DOUGLAS
[Read August 10, 1897.]
This is one of the most important matters connected with gardening, for by cross-fertilisation all the beautiful Auriculas, Carnations, Pinks, Gladioli, &e., have been produced; although until quite recent years the importance of the subject has not been recognised, nor has any record, that I am aware of, been kept, of the first attempt at hybridisation of any of our florists' flowers, which in every case must have preceded crossfertilisation.
The selection of varieties, from seed of the original wild parent, is a very slow process indeed, and but little would be accomplished in a life-time in this way. Of course there are exceptions. The Shirley Poppies, for instance, were produced by selecting the most beautiful varieties in each year from a sport of the original wild poppy of the fields, and in a very few years the Rev. W. Wilks brought up to one of our meetings the beautiful but fugacious flowers known as the Shirley Poppies.
On the other hand, take the garden Cineraria, well known as one of the most showy of spring flowers for greenhouse culture. I have grown the supposed original parent for four seasons, and have kept the plants isolated so that no pollen from any other Cineraria could touch the flowers; seed has been saved, seedlings raised and flowered annually, but there is not yet any appreciable variation from the original C. cruenta. In passing, I might mention that it is much more difficult to obtain seed from C. cruenta than it is to save it from the garden varieties. The plant was figured in the "Bot. Mag." about a hundred years ago, and the editor remarks that its seeds usually prove abortive. But if the plant when in flower is fertilised with pollen from the garden varieties, seed is produced more freely, and the prepotency of time pollen parent is evident in the progeny, which comprises many beautiful forms more like the pollen than the seed parent. The question has not been determined whether the garden varieties of the Cineraria have been obtained directly from C. cruenta by selection, or whether they have been obtained by cross-fertilisation with some other species. Some incline to one view, some to the other; I suspect cross-fertilising by some other nearly-allied species gave the first varietal forms.
The Gladiolus is another favourite garden flower which has been much improved by cross-fertilisation. The late Dean Herbert published a book on bulbs just sixty years ago, and therein gives an interesting account of his efforts in cross-f ertilising the Gladiolus. He made many crosses with distinct species, which he has recorded in his book, but he did not advise his readers to rest there. He says: "It is not, however, by crossing different species, or local varieties of plants only, that the cultivator may add to the beauty of his collection. Much may be done, undoubtedly, by crossing judiciously the finest seminal varieties of such plants as have already been improved in our gardens, and are disposed to break into a multiplicity of forms and colours." Dean Herbert is undoubtedly right. It is by first hybridising nearly-allied species, and then by saving seeds from the progeny and selecting from the plants resulting therefrom, that our garden favourites have been so greatly improved. Whenever variation has once been obtained, cross-fertilisation may be proceeded with to obtain further garden varieties.
It is thus that so much of beauty has been obtained in the Carnation and other garden flowers by amateurs who make one particular flower their study, and perseveringly work upon it year after year, not disheartened by failure nor unduly elated by success. I may be allowed to allude to the Rev. F. D. Homer as an Auricula specialist, Mr. Martin R. Smith as a lover of Carnations, and the Rev. G. H. Engleheart who has taken such infinite pains with the Narcissus. These gentlemen, and others like them, have, by years of perseverance, accomplished each a work that may last for generations yet unborn.
I know something of the Carnation myself, and have watched the progress made by Mr. Martin R. Smith, in his garden at Hayes. There is an accurate record kept of the result of all the various crosses, and much knowledge of a permanent kind has thus been treasured up for future use.
The old florists did good work in their days. Take the Carnation, for instance. I find it is stated in Rea's "Flora," published in 1676, that many fine varieties had already gone out of existence or had been pushed aside for new and improved varieties. Rea enumerates 860 varieties of Carnations in cultivation 221 years ago. These, of course, have long since passed away, having been replaced by other and doubtless improved forms produced by florists, who have left us the results of their work, but have given us no indication whatever as to how it was done. But we have evidence that quite as good varieties of the Show or Flaked Carnation were in existence 110 years ago as we have in our gardens now. There is a plate of Franklin's 'Tartar' published in Curtis's "Bot. Mag." in 1787. I showed this coloured figure to Mr. B. Simonite of Sheffield, the leading northern raiser and grower of this class of Carnations, and he was compelled to admit that no finer variety of this class was now in existence.
Mr. Martin R. Smith has informed me that he has learned from his own work at Hayes that the pollen parent has more influence in giving colour and form to the resultant seedling than has the seed parent. He says, "The prepotency of the pollen parent is beyond doubt," although I observed, in looking over his numerous experiments, that it was not invariably so as will be seen from the two following tables, which I have drawn up from his notes and records. My own experience is somewhat similar; and I have come to the conclusion that not only in the Carnation, but in all other florists' flowers, we must choose as a seed-bearer a plant with good habit, sound and vigorous constitution, and the variety from which the pollen is taken should possess flowers of fine form and of decided colours, all the better, of course, if the plant possesses a good habit and sound constitution also.
In sending the notes from which the tables on pages 208 and 209 have been compiled Mr. Martin Smith writes:- They are the result of observations since 1892, but I fear they are of a very negative character. Unfortunately the evidence on one side, viz., the prepotency of the female parent, must always be tainted by suspicion, for if the characteristics of the male parent are entirely absent it is so easy to urge that 'the cross was not a true one.' I can only say that we take the greatest care. We keep all bees out of the houses and never mark a cross as 'sure' unless the flower collapses within the proper time. When my records began, however, we were not so careful as we are now, and the bees had access to the flowers; thus a cross may have given evidence of its being 1 sure' by the collapse of the bloom, but we had no assurance that a bee might not have done the work five minutes before we fertilised the bloom. Taking, however, the general average I am certain that the great preponderance of flowers crossed and marked as 'sure' are really so, the evidence being often given by the habit and foliage when not apparent in the flowers of the produce. One very strong bit of evidence in favour of your theory is given by the crosses on 'Germania.' Now Germania is a flower of tremendous individuality, and if any flower in existence could transmit its peculiarities to its descendants it would be Germania; and yet you will find that Germania is swamped by the individuality of the pollen parent in the great majority of cases. I hardly ever get a yellow from Germania worth having. I get plenty, but when I do I find them, as a rule, pure reproductions on a most feeble scale of the mother, and I always regard them as products of Germania self- fertilised, and not a true cross."
TABLE I.—SHOWING PREPONDERANCE OF MALE PARENT.
|Seed parent||Pollen parent||Remarks on produce|
|Germania||Sir B. Seymour||All the produce took after male parent.|
|"||A maroon||Nearly all the produce maroon.|
|4 out of 5 were white.|
(yellow ground fancy)
|Produce took after the male.|
|"||Mrs. Vernon Harcourt||5 scarlets, 1 maroon.|
|"||Abigail (rose)||Rose, apricot, or buff barred with rose.|
|"||Ariadne||Produce scarlet, crimson, and rose.|
|Produce buffs and some rose.|
|"||Pink Malmaison||Yellow not represented exc. by buffs and buff ground fancies, produce giving every variety of scarlet, crimson, and rose.|
|"||Several purples||Produce mainly maroon, and white.|
|Sigurd (buff)||Germania||4 yellow, 2 buff, and 1 white.|
|Remembrance||"||All yellow ground picotees and fancies.|
|Audrey Campbell||Lady Gwendoline||1 white, 1 rose, 1 scarlet.|
|The Beau (buff) .||Germania||4 yellow, 2 buff.|
|Alice Ayrcs .||"||1 yellow buff.|
|Winifred (buff)||Rose Wynne
|Produce mainly maroon.|
|Almira||Pink Malmaison||4 pink, 1 yellow ground picotee.|
|Warocque||Almira||Nearly all buff, flaked and barred with crimson.|
|Scarlet seedling||Duke of Orleans||2 yellow, 1 buff, 1 crimson.|
|Corunna (yellow)||Hayes' Scarlet||2 white, 1 scarlet.|
TABLE II—DOUBTFUL OR SHOWING PREPONDERANCE OF FEMALE PARENT.
|Seed parent||Pollen parent||Remarks on produce|
|Germania||King of Scarlets||2 yellow ground picotees, 1 yellow self.|
|Hayes' Scarlet||Duke of Orleans||2 white, 2 scarlet. No yellows or buffs.|
|Ruby||Germania||2 rose. No trace of yellow.|
(crim. fl. maroon)
|,,||4 white, 1 maroon, 3 yellow or buff.|
|Governor||,,||1 yellow, 1 buff, 2 rose, 1 crimson.|
|Madame Van Houtte||,,||All took clearly after the mother.|
(maroon fl. crim.)
|,,||8 all following mother. No trace of father.|
|Tournament||Pink Malmaison||4yellow ground fancies, lrose self.|
|Countess of Jersey||Hayes' Scarlet||4 yellow ground fancies.|
|Abigail||Germania||2 white, 1 pink, 2 apricot, 1 yellow ground picotee.|
|Spy (white)||Mephisto||3 white, 2 rose.|
|Warocque||Gerinania||Every sort of colour, the nearest approach to yellow being buffs, self or flaked, and crimson. Almost all take after mother, and all very vigorous except those showing trace of father, such as apricots, buffs, &c., which are distinctly of weaker constitution.|
|Agnes Chambers||Abigail (rose)||2 yellow grd. picotees or fancies.|
|Ariadne (chaundy)||Germania||3scarlet, 3rose. Notrace offather.|
|G. C. Murray
|,,||4 white, 9 all colours, but not one with trace of father.|
|Mrs. Muir||Warocque||3 white, one of them blush.|
|Favourite (pic.)||Germania||6, not one with a trace of father.|
|"||Hayes' Scarlet||4 white ground picotees, and 1 white self. No trace of father.|
|Mephisto||Germania||1 purple, 2 dark maroon, 2 buff, 1 blush white.|
|Favourite (pic.)||King of Scarlets.||2 picotees.|
|Germania||4 maroon selfs. No trace of father.|
|Corunna||Port Light (scarlet)||3 yellow, 1 scarlet.|
The Auricula is a flower that I have carefully cultivated and crossed with the intention of producing seedlings superior to the parents; but I must confess that no better opportunity could be afforded to anyone who keenly desires to practise patience than by attempting to raise Show Auriculas.
The Show Auricula, as some of you are aware, is divided into four classes—viz., Green-edge, Grey-edge, White-edge, and Selfs. The Green-edge has the margin of the corolla green, without any spot or symptom of farina. Next to this margin of green is a ring or band of dark maroon; some are almost black. The centre is white, caused by a very dense coating of white farina; and the mouth of the corolla is a bright deep yellow. The Auricula fancier knows the points of his flower, and if desirous of producing a new variety with a green edge, he takes the two best he can get and cross-fertilises them. The process is first to remove the anthers from the intended seed-bearer before the pollen cases burst. After two or three days the pollen should be carried on a small brush, and placed on the stigmatic part of the intended seed-bearer. This is done three days in succession, and generally a cross is effected. The young and ardent florist may fancy he is to have a fine lot of Green-edged Auriculas, but if his expectations are high they will soon have a fall. Not one in ten will have a pure green edge, and if he gets a really good one out of 500 seedlings he may rest and be thankful; and that he may not be too overjoyed at even this limited success, it may be as well to add that a good seedling will not always retain its first promise of high-class quality, but often sadly degenerates after the first year's bloom. On one occasion, some twenty-five years ago, I cross-fertilised a fine Grey-edged Auricula, 'George Lightbody,' with pollen from 'Smiling Beauty,' a fine white- or grey-edged variety. There were about 1,000 seedlings flowered from this attempt. I saved about half-a-dozen promising varieties for further trial, but they had to be discarded one after another until only one remained; but it is still cultivated by amateurs under the naine of ' Silvia.' Some years afterwards I made another successful cross with the best greenedged forms, and after a very nearly similar weeding-out, I produced 'Abbe Liszt,' which is considered one of the best green-edged varieties.
Of course, the seedling-raiser of any type of florists' flower must have a standard of excellence before him, and the qualities or points he aims at must be in the parents; in both, if possible, but certainly in the pollen parent. Those intending to begin the culture of any florists' flower, and wishing to produce seedlings, will find the points of quality faithfully described in a recent publication of this Society entitled "Rules for Judging."
Another point I would like to bring forward, and, if possible, would like to have some discussion upon, is whether there is a point beyond which we can no further go. I not only believe there is, but bring some evidence in support of my contention. There is a picture of a bizarre Carnation taken by Sydenham Edwards 110 years ago; and the leading grower and raiser of this class of Carnation assures me that it is not yet surpassed. The Grey-edged Auricula 'George Lightbody' was raised from cross-fertilised seed fifty or sixty years ago, and cultivators north and south have been trying ever since to raise a better grey-edge, but have not succeeded in so doing. I do not for one moment allege that we can go no further in any direction with either Carnations or Auriculas. For in Self and Fancy Carnations, and Yellow-ground Picotees, there is still much to be done before any flower can be named perfection; but in some directions, notably in those I have mentioned, it almost seems as if we could not advance further. All the more reason that we should branch out in new directions, and continue to work on steadily and perseveringly in those directions where improvement is manifestly still possible.
It is not altogether easy work, for, besides the difficulty in raising new varieties better than the old, there are so many insect pests and fungoid diseases which must be fought and conquered. Our Carnations have the wire-worm boring the stem below ground, and the maggot above ground. Fungoid diseases, in winter of one kind, and another species in summer. The Auriculas have the woolly aphis, which is more than enough, and the Hollyhock is decimated year after year by a horrible fungus which attacks the leaves, and follows the plant everywhere. I verily believe if Hollyhock seed was taken and sown in Nova Zembla or in Patagonia the Puccinia malvacearum would be found ready waiting to attack the plants. But nothing daunts the enthusiastic amateur or the real lover of plants ; his failures or successes are but stepping-stones to the point upon which he has set his mind, and his motto is Labor omnia vincit.
Dr. MASTERS, F.R.S., drew attention to the coincidence that at the very time when Mr. Douglas was reading his paper a statue was being unveiled at Shrewsbury to the memory of Charles Darwin, and reminded the meeting of the great value and importance of the experiments and investigations with regard to the fertilisations of plants which Mr. Darwin had made. Darwin, he said, had been one of the first to point out the significance attending the slightest variations observed in plants, and he placed great emphasis on the fact that they were none of them the outcome of mere whim or caprice, but afforded evidence of the greatest possible value to students inquiring into the laws of design, environment, &c., as they affected plant life.
Mr. A. DEAN advised using seedlings from Germania as pollen parents in crossing Germania, as he fancied that a better Germania could only be obtained by either self-fertilisation or by crossing with its own produce, or possibly with some other good yellow.
Mr. COLVILLE BROWN stated that he had raised a great many seedling carnations from Italian seed, which all produced single flowers the first season of flowering, but that many of these became semi-double the next season, and quite double the next.
Mr. JENKINS, referring to the supposed prepotency of the pollen parent, said that he had crossed two of the best white flowers, and the seed so obtained produced flowers of almost all colours, even some scarlets among them.
Mr. DOUGLAS, replying, mentioned that "Purple Emperor" was obtained from two white wire-edged picotees which had been crossed with a view of getting white ground picotees. He also said that for a single-flowering carnation to develop into a double one, was quite the vice versa of his experience.