Volume Number: 1  2  3  4  5  6  7  8  9  10  11  12 




Not long ago I received a tentative order for ten million clustered flowers in a single lot. The order came from a French milliner, who stated that unless he could get at least ten million blossoms he could not afford to handle them at all. I was too busy with other things to attempt to fill the order, but the fact that it was given is worthy of record as illustrating the more or less unexpected opportunities that open up before the plant experimenter. The flowers that the French milliner wished to use in such quantity are species of Composites known commonly as Everlastings. These flowers have long been popular because they retain their form and color more or less clearly when dried, and thus make permanent bouquets. In recent years, however, the abundance of fresh cut flowers has caused the everlastings to be much less popular than they formerly were. Now, however, it appears that a process has been perfected through which, by chemical treatment, the dried everlasting flowers are given a degree of permanency and toughness of fiber that makes them suitable for use in trimming hats. Moreover, the grace and beauty of the new Australian star-flower are qualities not possessed by any other everlasting. Hence the milliner's desire to secure them in quantity. Although I could not undertake to meet so comprehensive a request, I have nevertheless been experimenting for a number of years with various tribes of everlastings. These are plants that originally came from the Cape of Good Hope, and are hence known commonly as the Cape everlasting. There is an Australian star-flower that is pretty closely related, which is also an everlasting, and it is with this that my chief work has been done. This was sent me by my collector in West Australia, who first discovered it. With the more familiar tribes of everlastings I have been well acquainted since boyhood, but it is only in recent years that I have given them serious attention. They are of many colors-red, pink, crimson, yellow, orange, and white. Some of them that are annuals in the eastern states became perennials in California, even growing throughout the winter. The everlastings with which I have experimented most extensively belong to the genus Helipterum, and are known to the horticulturist as Rodanthes. My work commenced with a so-called double Rodanthes, which varies from white to red in color. The seeds that furnished the original stock were said to represent a double flower, but only a small proportion of the plants that grew from them bore flowers that were really double. That is to say, there was almost invariably a center devoid of petals. My work consisted in selecting to fill up the center, and make a flower that is altogether double. The flowers vary much in size, and the colors are so variant as to supply good material for selection. But a difficulty arises in that the plants produce very little seed. My selective experiments have now extended over a number of years, and I have been able to increase the size of the flower, to improve it considerably in the matter of doubleness, and to isolate to a certain extent the different colors, although the plant as yet is not fixed in any of these regards sufficiently to justify its introduction. The improvement already shown, however, justifies the expectation that varieties of this everlastings could be developed that would show marked improvement over old types. I am experimenting also with everlasting flowers of various other genera, including a Gonohrena, the seed of which was received from South America. This plant has been under cultivation for many years. It is a low growing plant, having globular, crimson flowers. The introduction of new blood from the wild South American representative may be expected to have the usual stimulative effect, increasing the vitality of the plant, and perhaps urging it to greater variation. The Australian star-flower first mentioned in this chapter most resembles Rhodanthea, but is as distinct as a rose is from a carnation. The botanists have not been able to decide as to its specific name. With the exception of the Rhodanthea, this is without doubt the most beautiful of all the flowers called everlastings so far discovered or produced. The beautiful star-shaped, rosy-crimson and white clusters of flowers, produced in the greatest abundance, are surpassingly beautiful. The plant is an annual, produced only from seed. The reason that this flower has not been more generally grown all over the world is that it is peculiarly subject to the attacks of soil fungi. On virgin soil it always thrives; on cultivated soil, sometimes. There is no doubt that this most beautiful of everlastings can finally become immune to fungi in cultivated soil through selection. My work with the Australian star-flower has consisted of increasing the size of the blossom, making it semi-double, giving it added brilliancy of color, and to some extent rendering it resistant to disease. This has been accomplished by the usual method of selection, strings being tied about the better specimens, and finally the one best being saved for seed. Very great improvement was made, considering that this was a wild plant never before under cultivation. The selected varieties do not as yet breed true from the seed.


In an earlier chapter mention was made of hybridizing experiments in which certain members of the amaryllis tribe were crossed with certain of the Crinums. It is desirable to make additional reference to some experiments in which the crinums themselves were variously developed and hybridized with rather striking results. The hybrid Crinums are a really splended group of bulbous flowering plants in which the bulbs are in many cases of enormous size, and the leaves are broad and long, making the plants very conspicuous. Some of the leaves, indeed, are of gigantic size, and the stalk that bears the flowers may grow to a height of from four to six feet. The flowers themselves are of variant color, from white to rosy pink, and sometimes almost purple. They are borne in profusion, and their attractiveness is often enhanced by their fragrance. The crinums were originally residents of the tropics, being indigenous to various parts of South America, the southern United States. There are several species that are hardy in California. In some cases they will withstand freezing, so that even if the leaves are destroyed by the frost the new growth will put forth in the spring, and they will bloom as abundantly as if they had been carefully housed over winter. Like most other bulbous plants they thrive best in sandy soil. Some of the crinums are evergreen under ordinary temperature, others are deciduous like most of their relatives of the amaryllis tribe. The chief objection to the crinums for house culture is the enormous size of the bulb, and the tendency to produce a superabundance of foliage out of proportion to the number of flowers; although this criticism does not apply to all of them. Ten or twelve years ago I had probably twenty species of crinums, some of them having been brought from the tropics. My object was to combine the good qualities of the tropical and sub-tropical species with those of the hardy ones that had become acclimated in California. No difficulty was experienced in crossing the various species, and hybridization was carried out in the usual way, different pairs of species being mated and then the hybrid forms in subsequent seasons remated, noting of course at all stages which combinations seemed to produce the best results. Mixed hybrids were finally produced that combined the strains of many species. The results were highly interesting. In the course of a few years I had a strain of crossbred crinums presenting most of the desirable qualities of the different species in combination. The new plants, in spite of the strains of tropical species in their germ plasm, are very hardy, withstanding the coldest weather of this region without injury. They have very large flowers, varying in color from white, pink, and rosy crimson to purple. The petals are broad, and the flowers in a large number of cases are fragrant. The bulbs of some of these hybrids have taken on extraordinary growth. At four years of age some of them are from six to eight inches in diameter, and twelve to eighteen inches in length, weighing probably from ten to fifteen pounds, or even more. More recently specimens have appeared of even larger dimensions. Some of these enormous bulbs seldom make offsets, others produce from one to twelve or more offsets in a season, so that they can be multiplied quite rapidly. The seedlings from these hybrids produce plants that as a rule show a combination of two or more of the species fairly well balanced. The seed parent of the larger number of my hybrids is the Crinum Americanum, but in some cases the Crinumn amabale, or the Crinumn Asiaticum was the seed parent. It is observed that a certain small percentage of the hybrids show a strong propensity to run toward the seed parent of whatever species. This can generally be detected by the foliage when the plants are quite small. I have not observed that any of the hybrids depart so strongly the other way toward the tropical species (the pollen parent). In the second and third generations the variations are better balanced through selection, and become more fixed in desired qualities than at first, when grown from seed. On the whole, it is perhaps a little easier to get new species of crinums by crossing and selection than with most other bulbous plants, especially the lilies - although there are notable exceptions among the California lilies, some of which cross very readily. I have sold a number of the hybrid varieties of crinum, but they have been introduced unnamed, or at least were not named by me. The crinum seeds are very curious, in that they vary enormously in size, almost always in the same capsule. The pale-greenish bulblike seeds with irregular corrugations may vary from the size of a pea to that of an English walnut. When placed in a graded sequence they present a curious contrast. Yet the plants grown from the smallest seeds are likely to be quite as large and of the same appearance and quality as those grown from the mammoth ones. The seeds of the crinum thus furnish a unique link between seeds, buds, and bulbs, suggesting the properties of all these combined. Another peculiarity of the seeds is that they contain so much nutriment and moisture that they may sprout and grow, making plants of considerable size, without access to any moisture except that contained within the seed itself. I have known them to sprout when laid on a shelf, or in envelopes, away from the light and entirely dry; also when sent to me by mail from Australia they sometimes started as seeds and arrived here in envelopes as small growing plants. The crinums have been under cultivation for a long time, and interesting hybridizing experiments were made with them a century ago by the Rev. W. Herbert, Dean of Manchester, whose experiments with the gladiolus and other flowers have been elsewhere referred to. But there are many species that have not been so largely experimented with, and the opportunity to introduce new forms from the tropics, together with the striking character of the plants themselves, gives them peculiar attractiveness for the experimenter. The possibility of making still wider hybridizations, as in the case of the cross with the amaryllis, and further selections, should of course not be lost sight of.


Another tribe of bulbous plants that have great interest is that represented by the genus ixia. These, like so many other of the interesting bulbous plants, are natives of the Cape of Good Hope, and they are closely related to the gladiolus, and resemble many other Cape bulbs, including the Watsonias. There are various species, but they have been so intercrossed and mixed that the experimenter need pay very little attention to specific names and distinctions. The bulbs are inexpensive, and are commonly grown several in a pot in the house in winter in the eastern states, but in California they grow outdoors, and there is no occasion to transplant them, except for propagation. A single bulb will spread by putting out new bulbs, which in turn make offshoots in the same way, until a large and beautiful clump of plants is often developed. The ixia, indeed, can never be seen at its best except when grown in this way. The flower stems are thrown up in great abundance on long, stiff, wiry stalks, and the graceful upright or drooping flowers are of every color except blue-crimson, yellow, and white being the characteristic colors. The variety of ixia known as the Wonder has double flowers that are exceptionally handsome. The group of ixias make so striking an appearance that they compete with the giant amaryllis in my gardens in May for first place in their appeal to the average visitor. The two plants are utterly different, but each in its way is most individual and striking; the ixia being characterized by gracefulness and fragile beauty, the other by its massiveness. The flowers of the ixia are only about two inches in diameter; those of the others eight to ten inches, yet the massed effect of the ixia is so striking that it competes in interest with the larger flower. I have worked in a more or less desultory way on the ixia for the past dozen or fifteen years. The varieties under cultivation are so mixed as to their ancestry, and hence have so strong an inherent tendency to variation that it is not necessary to cross them. Even the double variety is probably at least half a century old. My work of improvement looks to the increase in size and brilliancy of color of the flower; and, of course, here as always, attention is paid to gracefulness and abundance of blooming, and vigor and general health of the plant. The improvements in all these regards have been quite striking, although I have not considered any individual variety worthy of introduction under a new name. Notwithstanding the amount of work that has been done with them, the ixias will well repay the attention of the amateur who cares to work with them.


In an earlier chapter an account was given of my blue poppy. An account has also been given of the development of new colors in the flower usually called the California poppy, but more properly known by the somewhat forbidding name of Eschscholzia. Very little has been said, however, about the experiments with the well known annual and perennial poppies, which have produced some results of considerable interest. The poppies in question are the opium poppy (Papaver somnifera), and one previously called the Oriental (Papaver orientalis). The opium poppy is, as everyone knows, a commercial product of vast commercial importance in the Far East. It has been under cultivation in Europe to a greater or less extent for several centuries, and has been greatly improved by the European growers, the varieties developed being of almost every shade of color, some flowers being single and others double. From time to time charming varieties have been sent out in recent years, including an interesting single one known as the Miss Sherwood, a variety having blossoms with a white center and crimson edge, the petals being beautifully fringed. There are other varieties known as Paeonia and Carnation Flower poppies that are double and are exceedingly handsome in color. The Oriental poppy has very large flowers, always crimson with shadings of scarlet in color in a state of nature, and in almost all cultivated varieties-the color being unusually well fixed. The plant is a perennial with rough, hairy leaves. The flowers are borne on single stems, instead of branching from a main stalk as in the opium and most other poppies. The Oriental species has probably not been under cultivation as long as the other, but many varieties have been developed, some of them semi-double, and the colors have been modified so that there are dull white, scarlet, and yellowish varieties, as well as the more usual crimson. These varieties, however, seem not to be well fixed-they do not come true from the seed-and the best varieties so far produced quite generally appear to be lacking in vitality- possibly from overzealousness in selection by division, the only way of maintaining and multiplying any special variety. My own experiments have largely had to do with hybridizing the Oriental and the opium poppies. Rather curiously I found that the pollen of the opium poppy was ineffective when used on the Oriental, yet when a reciprocal cross was effected, the pollen of the Oriental being used oni the opium poppy, seed was produced, and a great number of hybrids were soon under observation. In the hybrid colony, comprising more than thirty thousand of these plants, there was as little variation in color as is usual with the Oriental poppy. None of the hybrids were double, but they had several interesting qualities. One striking peculiarity was that the hybrid poppies produced in some cases enormous seed capsules, five or six times as large as the ordinary seed capsule of either parent species. Yet in other plants the seed capsule would be smaller than that of either parent. In still other cases twin capsules are produced uniformly, and with a certain number there was produced a mere rudiment of a capsule. But the most striking of all were the numerous plants that produced not even an intimation of a capsule, the flowering stem ending abruptly like the end of a lead pencil. All in all the hybrids showing this extraordinary variation in the seed bearing capsule-ranging from enormous enlargement of the capsule to its entire obliteration-make a very wonderful and interesting study in heredity. It is of further interest to note that, although these hybrids were raised from seed of an annual poppy (hybridized, however, by a perennial), yet without exception every member of the entire company of thirty thousand is a perennial. The flowers, themselves, vary greatly in size, some of them being seven or even eight inches in diameter, while the smallest are perhaps only four or five inches. Some are beautifully crimped, others have flat petals, there being the most striking variations in form. Even the specimens that have unusually large, plump seed capsules may produce no thoroughly well developed seeds. In a gallon of the seed-pods, from which one might expect perhaps two quarts of plump seed, I usually obtain perhaps from one hundred to three hundred or four hundred grains, mostly of shrunken ill-shaped seeds. Yet these shriveled seeds when sown produce good plants. Even seeds that seem so abortive that it is incredible they should germinate, may produce perfectly healthy seedlings.


The second generation poppies produced from these seeds were among the most remarkable companies of plants that I have ever seen. All who saw them agreed that they were the most variable lot of plants of a single fraternity that they had ever observed. The diversity was so great that it might be said that there were no two plants among the thousands that were even approximately identical. No two could be found in which differences could not readily be observed in the foliage. Some of the peculiar forms of leaf were these: (1) Long, smooth strap-shaped leaves sometimes not more than half an inch wide and a foot or more in length; sometimes smooth and sometimes villous; dark green or light green. (2) Short and stubby leaves, trifoliate, either villous or glaucous. (3) Leaves resembling those of the Oriental poppy. (4) Leaves like those of the opium poppy. (5) Nondescript leaves, variously suggestive of the leaves of primrose, cherry, dock, wormwood, dandelion, and scores of others. It is interesting to note that the blossoms of the second generation varied somewhat less than the leaves, although much more diversified than the blossoms of the first generation. Some were double and of various shades of the opium poppy. The range of color included almost black, deep crimson, purple, light crimson, salmon shades, pink, white, and various combinations of these colors. Yet on the whole the color variation was not greater than that ordinarily found in the opium poppy. The second-generation plants seemed not to have the vitality shown by those of the first generation. There were exceptions to this, however, individual plants manifesting a vitality in excess of the average of the first-generation plants. Most of the second-generation hybrids that produced double blossoms proved to be annuals or biennials, partaking thus of the characteristic of the parent from which they derived their doubleness of blossom. This is perhaps what might have been expected. It is notable, however, that the quality of annual or biennial growth should have reappeared in these hybrids of the second generation, the first generation hybrids having been, as already noted, all perennials. But, on the other hand, some of the second generation hybrids were perennials, and have continued to live and thrive, bearing large quantities of blossoms each season. Thus the perennial and annual habit appeared, in the case of these two poppies, to be a pair of unit characters of which the perennial habit was dominant and the annual habit recessive; there being a characteristic segregation in the second generation. As to habit of blooming, there was another interesting anomaly. The opium poppy, a strict annual, blossoms only for a short period-for a few weeks at most. The Oriental poppy, although a perennial, also blooms but a short time. The first generation hybrid poppies bloom persistently. There is not a day in the year when some of these hybrids are not in bloom, spring, summer, autumn, or winter-blossoms can always be gathered in quantity from them. The hardiness of the hybrids has not been fully tested. I should not be surprised to find that they are largely as hardy as the Oriental poppy, but the California climate does not subject them to a severe test.


In the third generation, a large number of the hybrids reverted toward one or the other of the original parents. But even those that resembled one of the parents or the other strikingly, retained also traits of the other parent. In this generation the plants mostly produced no seed, and the tribe partially ran out. All these unique hybrids present such interesting characteristics that it will be worth while to record that the opium poppy that was used as the original parent was of the Miss Sherwood variety, but that later other opium poppies of every shade and color that could be obtained were also used. Perhaps in all twenty-five or thirty selected varieties of opium poppies of various colors and different forms were used as seed parents. The progeny, however, as far as I could observe, varied little and was not greatly influenced by the different type of opium poppy used. However, the variation was so great in any event that it would be difficult to judge as to this. In general, the minor colorings and doublings of color seemed to have less effect in the heredity than the more fixed original foliage and flowers of the wild plants. The hybrids show doubleness and selected colors very slightly, except in a few cases in the second generation, when there was a tendency to return toward the original forms. It should be noted also that the Oriental poppy, although failing of fertilization when treated with pollen of the opium poppy, produced seeds abundantly when fertilized with its own pollen. The size of the pollen and length of the pollen tubes may conceivably have something to do with the failure to effect hybridization when the Oriental poppy was used as the pistillate parent; but this is only conjectural. Also, the opium poppy has been so long under cultivation, and has become so adaptable, that it perhaps is more pliable and more ready to receive strange pollen. The relative sterility of the first-generation hybrids may be judged from the fact that almost five thousand seedlings produced ten or twelve gallons of capsules, but that there was only about a quarter of a teaspoonful of seed to each gallon of capsules. As these seeds were shrunken and much smaller than ordinary poppy seeds, however, the actual number of seeds was proportionately large. Still the total number was only a fraction of what would have been the output of poppy plants of normal fertility. All in all, this experiment of hybridizing the Oriental and the opium poppies, with the production of relatively infertile hybrids showing Mendelian heredity as to some traits and a blending of characters as to others, and a further segregation and recombination of characters in the second generation, constitutes an unusually interesting experiment in heredity. I have made many other experiments in breeding the various poppies, but none perhaps that excelled this one in interest and importance.

This text is from: Luther Burbank: his methods and discoveries and their practical application. Volume 10 Chapter 5