Gamma Gardens: Atomic Plant Breeding

There is something fundamentally primal about gardening. Technology has infiltrated every corner of our societies, and yet, the garden seems far removed from the vicissitudes of modern life. When our fingernails are fringed with soil, time seems to melt away as seedlings slowly uncurl from their husks and leaves splay out to catch the sun. Gardening, if you can excuse the pun, is deeply entangled with our evolutionary roots. Sowing seeds, which we humans have been doing for millennia, rekindles both a connection with nature, and these days, a sense of nostalgia. Rarely do we see fruit on trees rather than in plastic crates, and our once-green thumbs scroll iPhone screens, but we still want our vegetables to come from gardens and not laboratories. We have qualms with transgenics and synthetic pesticides, anything that ‘messes’ with the sanctity of nature.

However, this moral weight that we ascribe to ‘nature’ is a relatively new phenomenon. The history of humans cultivating land hasn’t been nearly as wholesome as we might like to remember it. Agriculture has traditionally been the battlefield where innovation and cutting edge technologies emerged. Surprisingly, the legacy of some of the less brutal and simply bizarre attempts to modernise the industry can still be found today on our supermarket shelves, even if the stories behind them have been forgotten or romanticised away.

Image from the LIFE archives.

Following the aftermath of the Second World War, agricultural systems were struggling. Damaged resources and booming populations were putting increased pressure on farmers, who were scrambling to keep up with both the demand for produce, and the threat of disease wiping out entire crops.

A few decades prior to the war, at the beginning of the 20th century, geneticist Hermann Muller had discovered that exposure to X-ray radiation could cause mutations in the genes of fruit flies, changing their colour or growth. Occasionally, these changes could be passed down to the next generation. Researchers wondered whether these same strange effects could be found in plants, and indeed, they were. Essentially, ionising radiation helped to ‘shuffle’ genes around within cells, speeding up the process of evolution. Plants with beneficial mutations could survive and reproduce, passing on their new traits, and those that were affected in a negative way by the radiation simply died off. The plants themselves didn’t become ‘radioactive’, and no new genes were introduced, so they were perfectly safe to eat.

This was an intriguing result, but having just witnessed the incomprehensible tragedies that atomic bombs were responsible for, the general public was, understandably, skeptical of anything to do with nuclear technology. However, there was huge promise in the field, and governments and scientists were desperate to win back public approval so they could continue researching. In 1953, President Eisenhower instigated a campaign known as “Operation Candor”, to educate and reassure the public that nuclear technologies could be capable of more than warfare. This was partly a propaganda campaign to help fuel the arms race of the Cold War, but it also involved the foundation of Atoms for Peace. This project publicised a variety of peaceful and promising uses for atomic technologies  — and what better place to start than with agriculture, in an attempt to mitigate the effects of increased demand and disease which were causing food shortages worldwide.

Going off Muller’s idea that radiation could be used to shuffle genes and find new combinations and traits, scientists began constructing huge outdoor laboratory sites — gamma gardens — for their research. Mostly based in the US, these gardens were also built in the UK, Europe, India, Japan and Russia. Surrounded by high fences, the gardens were built in huge circular plots, covering up to five acres or more. Seeds were planted in concentric circles, separated into pie-slices of different varieties. Right in the middle of the circle would stand a tall pole holding up a radioactive isotope, usually cobalt-60, or caesium-137, which would send gamma radiation across the garden for six or seven months at a time. The pole could be lowered into an underground lead bunker when researchers came to take measurements.

Generally, the plants closest to the source would die, and further out many plants would be stunted or growing tumours, but around the edges, many plants looked normal. It was here that the researchers would discover which plants had beneficial mutations, giving their fruit brighter colours, bigger flowers, better resistance to cold climates, and so on.”

By 1955 August, an article in the New York Times claimed that “Irradiated Seed Will Make The Desert Bloom,” and publicity surrounding the technology as a possible cure for the world-wide food shortage became more and more enthusiastic. As the project drew more attention, many smaller research companies joined in, and curiosity blossomed into a growing movement to bring atomic energy and experimentation into the lives of ordinary citizens. Government subsidies allowed entrepreneurs and independent researchers to access nuclear sources and irradiate their own seeds that could then be sold to gardeners, school science clubs and families to grow at home. Any interesting effects could be reported back, in what was basically a nation-wide effort of citizen-science.

Photographed by Frank Scherschel in 1961, this Atomic Garden Exhibit showcased and sold hundreds of varieties of atomic cultivars. Image from the LIFE archives.
Dahlia “Ornamental Rays” was first cultivated in 1966 from seeds irradiated with a a cobalt-60 source. Photographs by Annie Spratt.

The seeds were advertised as being “atomically energised” and “atom-blasted”, and the public received them enthusiastically. Scientists were careful to warn gardeners not to expect miracles every time, but this was the dawning of the space-age, and the promises that atomic gardens could help eradicate diseases in crops and produce “tomato vines that could hold over 120 fruits” was certainly a lucrative antidote to the atmosphere of fear bred by the Cold War.

In 1959, an ‘Atomic Gardening Society’ was founded in the U.K. by Muriel Howorth, after she received an unusually large irradiated peanut plant as a gift. The society aimed to promote citizen science, and acted as “a cultural body for the guidance of atomic plant-mutation experimentation”. Even Albert Einstein was one of the patrons of her organisation, and in the following years, over 300 gardeners across the UK set up experiments using seeds from the society. By the 60’s, garden shows were full of irradiated seeds and atomically energised plants, and many new vegetable cultivars made their way into the supermarkets.

Eventually, as the connection between radiation and cancer became more widely publicised, the public grew wary of the technology (despite the plants themselves being no threat). Scientists too became frustrated with the randomness and unpredictability of the mutations, and the popularity of gamma gardening began to wane. Transgenics and genetic editing methods have since become the gold standard, but a few gamma gardens still exist throughout the world today, such as Japan’s Institute for Radiation Breeding, a few hours north of Tokyo.

Despite the imprecision of the technology, plant irradiation stemmed the development of over two thousand varieties of plants which are still used in agricultural production today, and many of these can be found in just about any supermarket.”

Some of the most common gamma garden harvests include most sweetcorn varieties, breeds of black bean, Reimi rice, durum wheat, the Gold Nijisseiki pear, which is resistant to black spot disease, and even the ruby red grapefruit, which is now the most common grapefruit in the world. If you brushed your teeth today, you might be surprised to hear that hundreds of thousands of peppermint plants were irradiated at the Brookhaven National Laboratory, until 1971, when a variety was discovered that was immune to the fungal disease Verticillium wilt. It is this disease-resistance variety, known as Todd’s Mitcham’s cultivar that produces most of the world’s mint oil, which is used in everything from toothpaste to chewing gum.

Many more examples can be found in the florist or nursery — hundreds of orchids, tulips, roses, snapdragons, dahlias begonias and carnation varieties resulted from radiation breeding, allowing gardeners to create bigger and brighter flowers than ever before. Many of today’s so-called heirloom varieties might have actually come from these gamma-mutated strains— and this isn’t necessarily a bad thing.  It’s easy forget that the idea of the ‘natural’ is something that really has never applied to agriculture. Irradiated seeds might not have solved the problems of the world, but humans have been growing, selecting and cross breeding plants for thousands and thousands of years, since 7800 BC at the least, and this process of coevolution will no doubt continue for thousands more.

Liberty Lawson is an eternally curious writer, philosopher and scientist from Sydney. She is currently completing a PhD exploring the intersection of art, ecology and conservation technologies. Liberty is the creative director of a journal called Holographia, a biannual interdisciplinary exploration of art, science and philosophy. Check out Liberty’s WEBSITE / INSTAGRAM

Photo from the LIFE archives. 1961.
Grapefruits, a mix of pomelos and sweet oranges, were first crossbred in the 18th century, and the Ruby Red Grapefruit was one of the first and most commercially successful fruits of the gamma garden, first cultivated in 1927 from seeds mutated with atomic radiation. Image by Hans Vivek.