‘Be your own Burbank’

Before turning to later and more overtly experimental methods of plant breeding (in that they involved the adoption of novel and as yet unproven techniques from genetics) and their adoption by amateurs, I want first to consider the status of plant breeding at the turn of the century. The emergence of a group of professional breeders gave rise to a notion of amateur plant breeding, and especially to the sense that this could be pursued as a rewarding leisure activity or hobby. The engagement of these (usually self-identified) amateurs in selection and hybridization to produce flower, fruit or vegetable novelties – often with explicit reference to the examples set by professional breeders – set the stage for the later adoption of less tested methods advanced by experimental biologists. In describing how and why laypersons engaged in plant breeding around the turn of the twentieth century, I draw attention to a few key features of this practice: the hybrid characterization of amateur breeding as both leisure and scientific labour, the application of methods newly sanctioned by growing professional communities, the development of a community of amateur practitioners inclined to share methods and experiences, and, finally, the adoption of ‘experiment’ as a term to describe breeding-related activities. Although in looking back from the twenty-first century we might not be inclined to consider the activity of hybridizing and selecting flower or fruit varieties as ‘experimental’, many amateurs adopted the designation of ‘experiment’ in large part to indicate the uncertainty of the outcome of their work, as well as its involving an intervention in the expected natural order.

I begin by way of an example: in 1910, an amateur plant breeder from the suburbs of Detroit wrote to the editors of Country Life, a monthly magazine devoted to rural living, to report on the results of twelve years' worth of what he described as ‘experiments’ in vegetable breeding. ‘I have produced several new varieties of tomatoes which seem to me better than I have ever tasted’, David Beyer began. ‘And I believe I have succeeded in getting into them some of the “blood” of eggplants and peppers’. Beyer described these as his ‘combination tomatoes’, produced through a process of grafting the branches of tomato plants onto those of eggplants and peppers.Footnote ¹³ The editors in their response expressed scepticism as to whether Beyer's tomatoes were truly combinatory in the manner he suggested. Not only did they ‘not detect any flavor of eggplant or pepper’ in the sample tomatoes sent by Beyer, but, as they pointed out, hybrids were rarely, if ever, produced by grafting and nearly always by cross-pollination. Yet they did not want to discourage interest in this work, and so took the opportunity to call attention to the ‘world of fascinating experiment … open to every amateur who wishes to produce new and better varieties of fruits, vegetables, and flowers’. A portable greenhouse, handbook of plant breeding, and a vision of what one hoped to create were the only tools they deemed truly necessary. ‘Don't gamble and don't scatter’, they concluded, ‘Study scientific methods’.Footnote ¹⁴

The letters both of Beyer and of the editors of Country Life – centred on the methods and aims of amateur plant breeding – reflected both the growing popular interest in plant cultivation in the United States at the turn of the century and its intersection with an increasingly professional and technical culture of plant improvement. Gardening and plant cultivation had become a more widely practised and more diverse set of activities in the late 1800s. This expansion had been encouraged by horticulturalists, reformers, and also a growing commercial seed and nursery trade over the course of several decades.Footnote ¹⁵ In a few major cities, horticultural societies organized around mid-century and promoted garden culture through exhibitions and other outreach activities. Such societies were decidedly upper-class in their membership, populated especially by educated men who took up horticulture (typically understood as speciality plant or garden cultivation) as an activity that demonstrated both their refinement and their good character.Footnote ¹⁶ Yet gardening also democratized in these years, reaching a more middle-class audience, for example as transport and communication networks brought Midwestern towns into the range of both mass-circulation publications and the East Coast seed and nursery industry.Footnote ¹⁷ In the decades after the Civil War, it became a widespread and popular national activity, encouraged by a mass of new horticultural publications and supported especially by the growth of suburbs with their attendant ideal of a detached home and ample yard.Footnote ¹⁸

The late nineteenth century had also witnessed a boom in attention directed to plant breeding. This boom drew equally on emerging scientific ideas and market opportunities. In the mid-nineteenth-century United States, breeding already encompassed a diverse set of interests: it was a business pursuit, a cultivator's necessity, and a leisure activity; a task undertaken by seed- and nurserymen, by farmers, and by gentlemen cultivators.Footnote ¹⁹ Late in the century, however, government funding for crop innovation and improvement generated impetus for breeding work at experiment stations and land-grant colleges, and markets for improved seeds and plants consolidated. With this greater institutionalization and economic demand came greater professionalization, and soon an increasingly professional group of breeders emerged with a commitment to improving methods as much as plant and animal varieties.Footnote ²⁰ The rediscovery of Mendel in 1900, with the acceptance and even celebration of Mendelian laws as the key to predictable breeding, encouraged these trends. It also encouraged the idea of breeding as a science and a profession, involving theoretical underpinnings and methods that could be mastered only with appropriate training.Footnote ²¹

Although breeding was increasingly described as a professional activity, it nonetheless remained appealing and accessible to practitioners with minimal experience. In light of the increasing number of trained professionals producing fruits and grains for market within the purview of government institutions or commercial enterprises, a notion of amateur breeding emerged. This was an activity to be pursued largely for leisure, though it did also carry the potential for economic reward. For those who doubted what could be accomplished by the novice in this area, there was a ready model for achievement: the best-known commercial plant breeder, the wildly successful Luther Burbank, was well known to have been self-taught.Footnote ²² Burbank received an extraordinary amount of celebratory attention in the American press beginning in the 1890s for his fruit and flower innovations, plants that included such marvels as the pitless prune, the white blackberry, and the spineless cactus, in addition to more straightforward achievements in fruit, nut and flower breeding.Footnote ²³ As such, he was an easy reference point for those hoping to underscore the methods and rewards of plant improvement to a general audience.

Many Americans celebrated Burbank as a pioneer in the science of breeding, and, like other pioneers, they considered him to have blazed a trail that they could follow. Books and articles produced about Burbank in the early decades of the twentieth century encouraged amateurs to try their own hand at ‘burbanking’ plants. These accounted for a significant portion of early guides to amateur plant breeding. ‘Every man his own Burbank’, one article declared.Footnote ²⁴ ‘Every woman her own Burbank’, countered another.Footnote ²⁵ The take-home lesson of such articles was clear. An ambitious amateur, using simple tools and methods, could imitate Burbank's many successes in fruit and flower breeding at home.Footnote ²⁶ This was an activity Burbank himself reportedly endorsed. ‘A single reader of this magazine may develop a new plant, or so improve an old one as to make of it a great and lasting benefit to the race’, he was said to have told one biographer. According to Burbank, ‘the modern amateur plant-breeder’ could with patience and attention ‘produce remarkable results’.Footnote ²⁷

Those who pitched plant breeding to the public, some of whom were amateur breeders themselves, agreed that it was an activity accessible to anyone with the time and patience to pursue it.Footnote ²⁸ The materials needed to participate were minimal: a very little space to garden and a couple of plants were the only absolute essentials. Although an image from Garden Magazine depicted an expansive and open country garden as the ideal haven of ‘the amateur Burbank’, readers elsewhere were assured that this would be unnecessary.Footnote ²⁹ Suggested alternative garden locales ranged from the apartment window ledge to the ‘cooped-up city back yard’.Footnote ³⁰ Amateurs were encouraged to invest in a minimal toolkit. Although someone as skilled as Burbank needed only his fingertips for transferring pollen and a grafting knife, it was thought that most beginners would also benefit from items such as a penknife, jeweller's pincers, a magnifying lens, a fine brush and a saucer – these were the tools for cross-pollinating plants in order to hybridize – and shears and a pan of wax and brush – for those who would also graft.Footnote ³¹ The methods provided in these magazines ranged from very basic steps, such as transferring pollen between plants with a brush and waiting for seed to set, to more complex tasks such as grafting seedlings onto older tree stock to speed up the time to fruiting.

Amateur breeders who attempted to produce new varieties through selection and hybridization were eager to report their results. Some, like Beyer discussing his eggplant-tomatoes, wrote to the same publications that had offered instructions in the first place. For example, one amateur wrote in 1903 to American Gardening to discuss his ten years' hobby of hybridization in which he focused on the development of a hardier orange.Footnote ³² The amateur William Haynes pointed out in a contribution to Good Housekeeping how ‘very simple a thing amateur experiments can be’ and described his own Burbank-style work in crossing snapdragons, using a fine brush to transfer pollen. The task Haynes deemed ‘no great work’, and he encouraged other gardeners to pursue plant breeding as he did. It was, to his mind, ‘a game for gardens’ and he asserted that, as his experiences and the simplicity of the methods demonstrated, one did not have to be ‘either a scientist or an expert gardener to become a plant breeder’.Footnote ³³

The ‘game’ was not always pursued solely for pleasure, however. Some amateurs aspired to improve plants in ways that might prove profitable, as in the hope of developing better-tasting tomatoes or cold-resistant oranges. No doubt many hoped to take advantage of the growing market for fruit and vegetable innovations that was frequently described as being open to breeders at all skill levels. ‘[I]f a new plant of sterling merit crowns one's efforts, there is always some opportunity to dispose of it for a good price, a satisfaction independent of that of having attained success in one's hobby’, encouraged a guide to hybridizing that appeared in Garden Magazine.Footnote ³⁴ In light of such advice it is no wonder that an amateur like Beyer would take pains to describe the merits of his tomatoes in such detail, noting that they would be ‘excellent for all cooking purposes, e.g., canning, catsup, jelly, etc., since they are not watery and contain few seeds. They are admirable for eating raw … They ship well’.Footnote ³⁵ Another subset of amateurs aspired to educate themselves, or, as breeding promoters emphasized most often, to contribute to the store of human knowledge. The Burbank enthusiast Henry Williams believed that every breeding attempt was an ‘experiment’ that would produce ‘results sure to be surprising and fascinating’.Footnote ³⁶ Amateurs were to consider themselves a valuable part of a growing science, for professionals could not possibly imagine, much less conduct, every potential cross. ‘Every country home should be … a sort of experiment station’, admonished one author in the sport and outdoors magazine Outing, ‘not only for the interest there is in it but for the contribution to the public. In horticulture just now we need a lot of new things, and someone must either discover or create them’. He advised his readers, ‘Be Your Own Burbank’, but clearly thought they could be Burbanks for the world as well.Footnote ³⁷ In short, amateurs were encouraged to take up, and indeed did take up, breeding for various reasons: as a form of leisure activity, in hopes of turning a profit or as a way of gaining scientific knowledge or contributing to horticultural science.

Most of the Burbank-derived articles presented techniques that had been used for over a century, now celebrated and discussed more widely.Footnote ³⁸ The characterization of breeding practices transformed rapidly in the first decades of the twentieth century, however, especially as Mendelian genetics – a set of ideas linked to new experimental approaches in biological research – came to be seen as the cutting edge of breeding work at American institutions. The effect of Mendelism on amateur practice was less extensive than that of Burbank, likely in part because some professional breeders deployed Mendelism as a tool for demarcating their activities from those of farmers or other improvers.Footnote ³⁹

Still, the application of Mendelian laws was not always seen to be beyond the purview of the amateur. Some tried to make this clear by translating new terms into more accessible language. As a 1911 article in the general-interest monthly Everybody's Magazine declared, science ‘had solved Mr Burbank’ and the mystery of his abilities in the garden. The author accused scientists of confusing the public by hiding the discovery ‘under a bushel of big words like homozygote, heterozygote, recessives, and so on’, and thus did his best to make clear to his readers what exactly the new Mendelian laws meant.Footnote ⁴⁰ Others fought the perception of Mendelism as an impenetrable field by describing their success in applying its rules. William Cockerell, a self-declared amateur gardener who had ‘long been interested in breeding experiments’, recounted in 1914 how he had found in the field one afternoon a red sunflower and thought he might be able to make a stable new variety out of it. The only thing to do, he declared, was to make crosses of it, ‘to know whether the red would be dominant or recessive’.Footnote ⁴¹ He made the crosses, calculated the ratios of colours in subsequent generations, and claimed to have by this method eventually produced not only a fairly constant red flower but also a pink one by cross-pollinating his red product with a white flower. These feats he attributed to his knowledge of the laws of heredity, which had enabled him to ‘predict in advance just what would happen’.Footnote ⁴² The lesson was clear, whether or not the story was entirely true: Mendelian genetics need not unduly intimidate the amateur.

Articles describing how to hybridize plants to create new varieties remained a standard of horticultural and gardening magazines in subsequent decades. Improvement through hybridization was also the stock-in-trade of amateur flower societies as these organized in the 1920s and 1930s.Footnote ⁴³ Members of the American Iris Society or the Empire State Gladiolus Society, for example, charted progress in flower cultivation and especially breeding through exhibitions and in writing; publications of these societies in particular make evident the participants' expertise.Footnote ⁴⁴ Within their chosen floral subfields, these individuals could easily be considered experts as well as amateurs. This was noted even by the chief floriculturist of the United States Department of Agriculture (USDA), Samuel Emsweller. In 1938, he attributed the majority of recent improvements in ornamentals to the efforts of amateurs, especially with ‘the garden club movement … an active stimulant to flower breeding’, as well as societies dedicated to specific flowers. He indicated that the USDA would bring new attention to flower breeding, spurred by these amateur achievements and by the knowledge that many Americans were sure to support the work.Footnote ⁴⁵

Efforts continued to be made to reach new audiences as well, to encourage anyone with a flower garden to see it as a site for experimentation. Readers of Popular Science Monthly in 1937, for example, encountered instructions on how to become a ‘plant wizard’, producing new plants and novelties with just a few simple and inexpensive tools. According to the author, it would be no trouble for the amateur working in his garden to follow the procedures; the challenge would be learning the basic Mendelian patterns of inheritance and the relation of these to cross-fertilization and inbreeding. The article echoed many of the same sentiments found forty years earlier in Burbank-inspired articles: the accessibility of the methods, the experimental nature of the activity, and the potential for significant rewards. ‘The act of cross-pollination can be accomplished by anybody’, the author emphasized. ‘The tools are simple. The laboratory and test plot may be a few square feet in the home yard. One might even produce a new geranium variety in a window box’.Footnote ⁴⁶

Welcome to ‘Mutatia’

Although the techniques associated with hybridization remained mainstays of both professional and amateur breeding, they did not continue to generate headlines at the rate they had in the first decades of the twentieth century. Subsequent waves of gardeners-turned-experimenters found inspiration in new techniques, some of which came straight from the workbench of the experimental genetics laboratory without having first been vetted by professional breeders. It is in these activities that the links between amateur breeding and other twentieth-century tinkerer or amateur experimental cultures are most evident. Those amateur breeders who took up the use of X-rays, chemicals and radioisotopes such as I describe here were well aware that neither professional scientists nor breeders had yet determined the most effective ways to wield these tools. Such uncertainty was not discouraging, but rather accounted for much of the interest in amateur experimentation. Amateurs were eager to test and explore the possibilities created by these tools, and to share their experiences with one another. Although they differed in the extent to which they sought financial gain or to make intellectual contributions through their work, most did agree that they were venturing into the unknown – and that doing so could be its own reward. The responses of professional scientists suggest still further the extent and purposefulness of this amateur engagement: rather than universally dismiss amateur practice as inconsequential, some scientists engaged amateurs to aid in testing techniques as widely as possibly (akin to a ‘citizen-science’ initiative), while others went public with their denouncement of amateur experimentation as dangerous and misguided.

The earliest example of a new experimental method introduced into plant breeding is that of X-ray irradiation. After several researchers demonstrated in the late 1920s the effect of X-rays and other radiation in inducing mutations, breeders too began to investigate the X-ray as a potential tool for the production of new varieties. Mutations, after all, were the source of variations that could set an individual plant apart from its ancestors; if the X-ray could produce these in abundance, perhaps it would speed up the work of plant breeders who would no longer have to hunt for rare variations in the field.Footnote ⁴⁷

As professionals pursued this lead, so too did amateurs. Arlie Toulouse of Laguna Beach, California was one such amateur, ‘a musician by trade and a botanist by hobby’, who found the idea of X-ray breeding particularly appealing. In the late 1930s, Toulouse took part of his garden hobby to the Santa Ana hospital, where X-ray operators agreed to irradiate a collection of his seeds and bulbs. These he used for the ‘more than 100 definite experiments’ carried out in his small garden, experiments whose primary aim he declared was to produce better food and more beautiful flowers.Footnote ⁴⁸ Another like-minded amateur had a more specific goal: breeding a ‘pure golden yellow carrot’. In the late 1940s, E.J. Richards, who described himself as a hobbyist carrot breeder, wrote to the geneticists at Cold Spring Harbor Laboratory in search of assistance with his experiment of knocking out the gene for red colour using X-ray radiation. He had access to a powerful industrial X-ray machine that he envisioned would speed up his progress toward the elusive yellow carrot.Footnote ⁴⁹

Or take the case of W.E. Bott of suburban Lakewood, Ohio, who brought into his garden a far more portable technique from the laboratory. An amateur at plant breeding, though an experienced chemist, Bott boasted in 1939 to the Cleveland Press of his successes in producing corkscrew zinnias, a snowball bush with ‘blossoms as big as a dinner plate’, and other floral novelties. The secret of these achievements, which he eagerly divulged to fellow readers of the Press, was application of a naturally occurring compound known as colchicine. Scientists had recently discovered that treatment with this chemical generated changes in the chromosomes of plants, which Bott believed opened new avenues for research. ‘The experiments are so new that the full capacities of colchicine are unknown’, Bott emphasized, and although he believed that conducting experiments with the chemical might prove economically rewarding this was not the most exciting aspect of the work. He rejoiced instead at ‘the field of experimentation it opens up to the most humble of amateurs’, who could work and study alongside the expert to discover just what colchicine could do.Footnote ⁵⁰ Bott was just one participant in a decade-long craze for chemical-based plant breeding. The fad originated in biological research laboratories in the 1930s but quickly extended to commercial breeding operations and also to domestic gardens where amateur breeders such as Bott made their own assessments of colchicine's value and potential uses.Footnote ⁵¹

The chemical colchicine had long been used in medical therapy, especially as a treatment for gout, but it was not until 1937 that it began to be used on plants as well as people. That year, a handful of biologists discovered that the chemical could be used reliably to induce the duplication of chromosomes in many plant species.Footnote ⁵² This proved cause for excitement. As plant biologists then understood, the multiplication of entire sets of chromosomes was an important aspect of plant evolution.Footnote ⁵³ Many biologists saw in colchicine a tool that would aid basic research in cytology, genetics and evolution.Footnote ⁵⁴ Their excitement, however, paled in comparison to that of plant breeders. Some of the most economically valuable cereal crops were known to be polyploids – they had multiple sets of homologous chromosomes; agriculturists hoped that colchicine might be used to multiply the chromosomes in important crops and thereby create new and still more valuable types. Breeders also envisioned using colchicine to cross varieties previously resistant to hybridization because they differed in chromosome number, and to generate fertile plants from normally sterile hybrids. Most spectacular of all, they discussed the opportunity to produce enlarged varieties of flowers, fruits and vegetables, because doubling the number of chromosomes often resulted in doubling the size of these plant features.Footnote ⁵⁵ The early research among biologists and breeders on colchicine garnered a considerable amount of publicity, most of it either sensational or nearly so. Newspapers and magazines celebrated the finding of colchicine's perceived evolution-enhancing powers and the likelihood that its use would significantly improve agricultural production.Footnote ⁵⁶

Colchicine had another attractive feature frequently mentioned in both scientific and popular reports: it was available for purchase, if not from the local pharmacy, as some articles claimed, then certainly from larger drug and chemical firms, and it was fairly affordable as only a small amount was needed to produce an effective solution.Footnote ⁵⁷ As a result, even from the earliest publications, interested amateurs felt able and encouraged to try their hands at manipulating chromosomes with colchicine.

A few scientists fostered this amateur interest through their own research. The geneticist Albert Blakeslee of the Carnegie Institution of Washington's Department of Genetics at Cold Spring Harbor, who would be credited most frequently for the discovery of colchicine's effects, claimed in his first publication on the subject in 1937 that ‘juggling chromosomes for the betterment of plant-kind is primarily a matter for the trained genetics engineer who knows the chromosomes with which he is working’. But he and his co-author Amos Avery went on to explain how one could obtain colchicine and what it would cost, as well as how to identify a tetraploid by examining pollen under a microscope, a task with which ‘any high school biology teacher’ could assist.Footnote ⁵⁸ Blakeslee succeeded in inspiring imitators. He reported having received by 1940 over 1,100 letters from plant breeders of all skill levels inquiring into techniques for applying colchicine.Footnote ⁵⁹ He continued to receive such inquires (which he responded to with a form letter outlining the basic information about colchicine) for years. In a letter that serves as a fairly typical example of this correspondence, a woman from Denver, Colorado wrote in 1945, ‘I am an amateur – a garden hobbyist but deeply interested in improvements in plant life’. After this introduction she cut right to the chase, requesting information on how ‘to use Colchicine in some experiments’.Footnote ⁶⁰ In addition to those self-described ‘hobbyists’ there were also individuals who sought specific improvements, and who likely had potential economic rewards in mind. For example, in one case a South Florida man, frustrated with the slow response of his local experiment station, wrote to learn how he might try colchicine to improve mangoes.Footnote ⁶¹

Another of the colchicine researchers went about encouraging amateur participation via a more direct route. The cytologist O.J. Eigsti found himself short on the experimental space needed to conduct his work at the University of Oklahoma in 1939. To address the problem, he extended his laboratory into the farms and gardens of the surrounding community, inviting what he called ‘laymen scientists’ to aid his research by growing colchicine-treated seeds and plants and reporting their results to him. Inundated by responses, he developed his research into an outreach effort national in scope with hundreds of participants.Footnote ⁶² According to one Science Service news report, ‘the cooperative efforts of interested garden-makers’ would help Eigsti determine if colchicine could be truly useful.Footnote ⁶³ The follow-up report eighteen months later seemed definitive. ‘Amateur plant breeders aid science’, declared the headline, a point illustrated by an image of soybeans that had been doubled in size through the efforts of Eunice Moore, a nurse from Tulsa, Oklahoma.Footnote ⁶⁴

Although the initial aim of the collaboration had been for Eigsti to learn from his amateur correspondents about the range of plants on which colchicine treatment would be effective, his perspective soon evolved to one of seeing the opportunity as being more instructive for his participants than necessarily valuable to his research programme. In one follow-up publication he and an assistant declared of their project, ‘it is a valuable method of education … By participating in this cooperative project, gardeners are learning the importance of the scientific method, and the biological facts underlying the origin of new varieties of plants’.Footnote ⁶⁵ This assessment suggests the extent to which Eigsti considered the project useful along lines similar to the perceived value of so-called citizen-science initiatives later in the twentieth century: much as scientists might gain through the collection of data by laypersons, the laypersons themselves were seen to gain by their education in scientific practices.Footnote ⁶⁶ Of course, Eigsti's volunteers may well have considered their participation in a very different light. They were, after all, told that they were conducting valuable, independent experimental research. They even had to sign a form that asked whether, where plants were treated with colchicine, amateurs were ‘willing to allow the University of Oklahoma to have control over any future economic possibilities of these plants’.Footnote ⁶⁷ With such encouragement it is likely that many indeed saw themselves more as experimental investigators than as subjects of an educational initiative.

Amateur plant breeders did not need direct access to professional scientists to pursue their interest in colchicine. For example, they could encounter ideas on how they might use the chemical simply by turning the pages of a newspaper or their monthly gardening magazine.Footnote ⁶⁸ As with selection and hybridization, many reporters emphasized that the work was quite suitable for the home garden, requiring no experience and no complex equipment. The science journalist Frank Thone repeatedly encouraged amateur participation in colchicine work in the pages of the Science News-Letter and in other Science Service reports.Footnote ⁶⁹ According to him, the basic requirements to start were few: ‘You don't have to be a Ph.D. in botany to make valuable contributions in the field of plant breeding. All you need is some seeds, a little colchicine – and plenty of interest in the subject, plus patience, and willingness to keep your garden-patch weeded’.Footnote ⁷⁰ Another reporter echoed the simplicity of the methods, suggesting to his readers, ‘If you have ever done any gardening, you might have an urge to try your own hand at changing chromosomes … In contrast to many scientific experiments, this one is easy to perform’. He continued with specific instructions for both soaking seeds in colchicine dilutions and applying colchicine directly to the flower buds of full-grown plants, things his readers could do in their ‘own back-yards’.Footnote ⁷¹ At least one commercial outfit offered for sale to amateurs an experimental guide that would aid their colchicine breeding efforts.Footnote ⁷² The aim suggested by many of these articles and advertisements was the production of valuable new types, but as the emphasis on experimentation and ‘changing chromosomes’ suggests, the sense of entering into the unknown – in this case tinkering with some fundamental component of living things – was likely to have been just as important. W.E. Bott, in his explanation of chromosome manipulation, described to readers how knowledge of the mechanics of heredity would ‘intensify the incredulity you feel at witnessing colchicine's power’, and one suspects it was just that power that made Bott so eager to deploy the chemical in his garden.Footnote ⁷³

Most of those who applied colchicine in their gardens were likely to have satisfied their personal curiosity in the attempt and stopped there, or else been disappointed in outcomes that were undoubtedly less spectacular than reports had led them to believe. Others, such as Bott, felt an imperative to share their results, generating through these community-wide knowledge. Another like-minded amateur, Kenneth Houghton of Dedham, Massachusetts, wrote to the popular American gardening magazine Horticulture in 1940 to describe the challenges he had faced in his colchicine experimentation. He had in the year prior tested its effects on lupins, shasta daisies and gladioli. His work had not produced anything of value – nearly every one of his plants had died – yet he thought ‘the difficulties encountered may be of interest’ to other readers and so offered them for general circulation.Footnote ⁷⁴ Other experimenters provided reports on their colchicine research to flower and garden societies, where an altered iris, lily or African violet was sure to be of interest.Footnote ⁷⁵

Amateur experimentation with colchicine was perceived to be significant enough in extent that alarmed scientists and professional breeders cautioned would-be experimenters that colchicine was in fact a poisonous chemical and could cause bodily harm if inappropriately handled. The Journal of Heredity had first attempted to pre-empt uninformed experimentation in an editorial published after Blakeslee and Avery's 1937 announcement.Footnote ⁷⁶ This warning was further fleshed out the following year. ‘Colchicine is being so widely used’, the editor noted, ‘that a repeated word of warning regarding its extremely poisonous nature may not be amiss’. The notice warned that even dilute solutions of the chemical would be damaging to skin if not washed immediately, and included a harrowing personal account from the editor, who had accidentally got colchicine dust in his eye.Footnote ⁷⁷ Haig Dermen of the USDA, who was at the time conducting extensive breeding work using colchicine, attempted another warning about the hazards of working with the chemical in 1940, likely sensing that public interest (and with it the number of amateur users) had only grown in the interim.Footnote ⁷⁸ Some professionals, such as the flower breeder Gordon Morrison, thought that such warnings did not go far enough – the public ought to know that colchicine was not the miracle worker that most articles claimed it to be.Footnote ⁷⁹ Other critics voiced similar concerns, complaining about having heard fantastical claims of ‘family-sized vegetables’ and ‘Shasta daisies the size of dinner plates’ being produced in backyards and even on fire escapes.Footnote ⁸⁰ These individuals fumed about the public being fed what they perceived to be misleading information that in turn led to amateur experiments. Their ire suggests that they saw a boundary between the activities appropriate for amateurs and those appropriate for professionals, and felt a need to demarcate these.

In the end, such critics need not have worried. The fortunes of colchicine rose quickly, but they fell almost as fast. Professional scientists and breeders enthusiastically took up work with the chemical soon after the 1937 announcement of its effects, using it across a wide variety of species and, as described here, experimentation among amateurs followed suit.Footnote ⁸¹ Within a few years, however, the researchers who had initially discovered and promoted the use of colchicine in plant improvement changed their tone. It became more evident that colchicine would not be a speedy shortcut to improved varieties but simply one tool among many available to the breeder for manipulating plant heredity.Footnote ⁸² One exception was in floriculture, where professionals touted the potential for straightforward and rapid improvement through colchicine for a longer period.Footnote ⁸³ The idea of colchicine experiments as a cutting-edge tool also persisted longer among expert amateurs, where its accessibility, ease of use and immediate effects seemed to continually generate new interest – and on occasion new plants.Footnote ⁸⁴ At the end of the twentieth century it was a technique still discussed in amateur circles as a means to improve plants ranging in kind from magnolias to marijuana.Footnote ⁸⁵

The persistence of colchicine also reflected in part the continued importance of novelty in both professional and amateur horticultural breeding, for colchicine remained useful chiefly as a means to generate new and different traits. Ideally, these would be the more vigorous blooms or bigger fruits or vegetables that breeders thought could be produced through the creation of polyploid types. However, in addition to potentially duplicating chromosomes, colchicine often caused other gene and chromosome changes that in turn led to distinctive plants. These random mutations, often called ‘breaks’ or ‘sports’ by breeders, were of limited use in agricultural breeding such as of grains and cereals. By comparison, they were a key component of speciality flower and fruit production, areas that were also more within the purview of the amateur.Footnote ⁸⁶ Horticultural breeders sought unusual forms such as double flowers or previously undocumented colours, or modifications in fruit that would make a variety entirely distinctive. Unlike agricultural improvement, with its focus on specific traits that produced better-adapted or more productive plants, horticulture was a sphere in which there was a very good chance that unusual or different meant better. This in turn offered amateurs and professionals alike a comparatively wide range of perceived successes and placed a high premium on mutations.Footnote ⁸⁷

In the interest it sustained related to its mutagenic ability, and the association of mutation with novelty, colchicine took its place among a whole suite of mutation-inducing tools inspired by research in experimental biology and endorsed by amateurs at mid-century. These tools ranged from X-rays to various toxic chemicals, from temperature extremes to radioisotopes. All were at different times celebrated as producing change effectively, quickly and easily – and as methods that allowed ample scope for amateur achievement in particular. For example, when the amateur plant breeder John James – a self-described ‘Frankenstein of flowers’ – instructed readers on how to become ‘creative gardeners’ in his 1961 Create New Flowers and Plants … Indoors and Out, he delineated four basic categories in which the amateur might successfully accomplish this: discovery, selection, hybridization and mutation. Whereas the first three were tried-and-true techniques, methods of inducing mutation were both thrillingly new and as yet unperfected. James described for his readers the application of colchicine and radiation, both of which he envisioned as promising routes to amateur achievement.Footnote ⁸⁸

James had been led into such work by his own tinkerer-like inclinations to see what kinds of change he could effect in plants, first undertaking a project in which he scraped the radium from luminous watch dials and exposed budding roses to this material. The process did not lead James to an improved flower – in his estimation ‘it was the most deformed, blackspot-susceptible rose I have ever known’ – but it did confirm for him that radiant energy could provide the basis for many future investigations in plant breeding.Footnote ⁸⁹

James was eager to initiate others into such activities with descriptions of how other amateurs might undertake their own such projects. Rather than recommend the radium experiment to his readers, he advocated some faster and safer methods of obtaining radioactive materials available by 1961. For example, he described how one could request small amounts of radioisotopes from the Atomic Energy Commission or from a local pharmacist. Lest this process intimidate potential experimenters, he made it clear that obtaining radioisotopes would be the most challenging part of the procedure. This otherwise required only rubber gloves, an eyedropper, forceps (ice tongs or a clothes pin substitutable), cotton, and some adhesive tape, and consisted mostly in placing a few drops of radioisotopes in solution on the cotton and attaching this to developing buds for varying amounts of time. Once removed from the plant, the radioactive cotton could be easily disposed of by burying it in a far corner of the garden.Footnote ⁹⁰

Another amateur whose experiences with mutation breeding spurred him to describe the methods for other enthusiasts was James P. Haworth, who invited readers of his book Plant Magic to join him on an exploration of ‘MUTATIA – the realm of the Mutants’.Footnote ⁹¹ Though he focused on colchicine as an ideal experiment for the beginner, Haworth did not see any reason for amateurs to limit themselves to this well-established technique. His survey of scientific literature led him to include everything from changes in temperature to X-rays and ultraviolet, to an array of chemicals, to mechanical forces such as centrifuging. Because X-rays and radium were a little dangerous, he advocated sticking to ultraviolet rays from a commercial sunlamp for radiation experimentation; his ‘mechanically minded’ readers could ‘rig up home made centrifuges to attain any desired speed’, though this was, he admitted, also not without potential hazard.Footnote ⁹² Again, the appeal was assumed to be in the sense of personal accomplishment gained through even the most simple of the experimental methods Haworth suggested. As he pointed out to those readers he inspired to experiment, ‘as you hurry home from office, factory, or school’, you would be watching seeds ‘which you and you alone have brought into being’ sprout and grow in your own home garden.Footnote ⁹³ Although professional breeders had new techniques that had to be performed in a laboratory, such as embryo culture, with its requisite expensive microscopes and precision methods, the ordinary gardener in his or her usual place could succeed with most methods. ‘[W]orking in our gardens’, Haworth summed up, ‘All of us, Mrs Jones down the street, Uncle John back in New York State, and you, and I’, could explore the experimental world of amateur plant breeding.Footnote ⁹⁴

As had other amateur breeding evangelists in preceding decades, both James and Haworth were keen to convince their readers that this was a field in which anyone could make a contribution, whether in the innovation of a new plant or in the development of a useful technology. ‘The field is wide open to all. Imagine the cumulative effect of thousands of hobbyists working on plant improvement. New ideas, new techniques, and new reagents will bring us a new horticulture’, Haworth declared.Footnote ⁹⁵ The amateur could devise a new method for the application of colchicine more effective than any used to date, or discover another chemical mutagen still more potent. He or she might innovate a new centrifuge just as easily as a new garden pea. James echoed this sentiment. He emphasized the significant role of luck in which mutation turned up and at what moment and the impossibility of predicting the exact product of cross-pollination – conditions that levelled the playing field between professional and amateur breeder considerably. Amateurs, in fact, might be more successful in innovating, because their judgement would not be clouded by prejudicial preconceived notions of what might or might not be possible.Footnote ⁹⁶

The ideas about induced-mutation plant breeding advanced by these two adventuring amateurs were not as uncommon or inaccessible as one might think. First, they appeared at a moment when mutation, and especially radiation-induced mutation, were concepts that carried heightened significance in American culture. In the post-war years, concerns about nuclear testing and potential nuclear war directed public attention towards the genetic hazards of radiation and fallout. While scientists debated the genetic consequences of the nuclear age within such forums as the National Academy of Sciences, popular productions such as the film Them!, which depicted giant mutant ants resulting from atomic testing, transformed radiation-induced mutation into a pop-culture concept.Footnote ⁹⁷

Second, the methods themselves were fairly accessible. Colchicine no doubt circulated most widely, since it could easily be purchased, but even irradiation would not have been difficult to pursue. In the 1960s, there were a number of routes for home gardeners hoping to try this method. As had X-ray experimenters since the 1920s, they could take seeds to their local physician for irradiation; Scientific American recommended this as a substitute for the gamma radiation applied in atomic laboratories.Footnote ⁹⁸ Here, too, the specific social and political configurations of the atomic age contributed to an expansion of the opportunities available to would-be mutation experimenters. With a significant amount of attention directed to peaceful applications of atomic energy, and the interest of the Atomic Energy Commission in ensuring the success of such applications, professional geneticists and plant breeders had ample state support to pursue studies of radiation-induced mutation and its use in agricultural activities, including plant breeding.Footnote ⁹⁹ Thus if amateurs were truly determined, they might reach out to the geneticists at Brookhaven National Laboratory, or to the cooperative irradiation programme of the Oak Ridge National Laboratory. Both of these had established seed- and plant-irradiation outreach initiatives in 1950s and 1960s as part of government and scientific emphasis on peaceful uses of atomic energy.Footnote ¹⁰⁰ Most convenient of all, the interested amateur could purchase Dr Clarence Speas's irradiated flower seeds at their local Walgreen's, or similar stock from Breck's Seed of Boston and other outlets. These were seeds that had been exposed to ionizing radiation of various types at the nation's atomic research sites. ‘Be the first to grow unpredictable “atomic” plants’, Dr Speas's advertisements proclaimed, ‘Join the worldwide search for new species by safe experiments in atomic science!’Footnote ¹⁰¹ Even if they weren't handling radioactive materials themselves, therefore, amateur gardeners could still participate in the experimental culture of atomic-era plant breeding – not to mention, of course, the larger culture of atomic celebration and promotion sanctioned by the United States government through the Atomic Energy Commission and later amplified still further by the International Atomic Energy Agency.Footnote ¹⁰²

Whether intrigued more by the idea of manipulating living organisms or by the novelty of atomic energy, many garden columnists enthused about these possibilities, much as they had about potentially revolutionary horticultural techniques in decades past.Footnote ¹⁰³ Those who did have a chance to try gardening with irradiated stock showed off their creations at flower shows and fairs.Footnote ¹⁰⁴ Others participated in the Atomic Garden Society, an organization established in the early 1960s in the United Kingdom and dedicated to the sharing of results and seeds from radiation experiments.Footnote ¹⁰⁵ Together these amateur breeders maintained a view of the garden as a domestic space of investigation and innovation, one that would not be intimidated even by so exclusive a technology as atomic fission or be limited to those activities that professional breeders had decades ago deemed safe, reliable and productive.

As these examples from X-rays to colchicine to radioisotopes show, many techniques and technologies for altering the genes and chromosomes of plants circulated outside the experimental biology laboratory, where they were put to use and celebrated by amateur plant breeders, often in their domestic gardens. They were accepted, with some scattered but infrequent objections, as useful and beneficial to amateur practice.Footnote ¹⁰⁶ That many amateurs described their work in terms of experiment and used scientific language suggests that they saw themselves as in conversation with scientists and with professional breeders, even as they engaged in breeding primarily as a leisure-time pursuit. Thus many aspects of the enthusiasm for the use of chemicals and radiation in breeding were reminiscent of that which had surrounded the work of Burbank at the turn of the century. These included an emphasis on the application of new scientific knowledge and advanced techniques in the production of improved plant varieties, the argument that this was a world of experiment and opportunity open to breeders of many backgrounds and skill levels, and especially the claim that great pleasure and satisfaction would be derived by the amateur from understanding and applying these techniques as part of their leisure time.

These aspects also link amateur plant breeding of the twentieth century to other amateur experimentalist or tinkerer traditions. Like those better-described groups, amateur breeders engaged in the exploration of particular technologies and recent scientific developments in the hopes of directing these to their own, mostly leisure-oriented, ends. This was often a communal activity, in that amateurs shared their methods and results in a variety of forums, whether clubs, newspapers, specialist magazines or even books. They were served, and encouraged, by similar popular-science and technology publications.