Through the centuries, plant-minded painters and photographers have explored the beauty of fragrant roses, exotic orchids and luscious fruit. In this lineup, the garden vegetable is bottom banana.

This is about to change. Fifteen years ago, the fates brought together two collaborators who are placing beets and onions and many other common edibles where they belong, on a pedestal. (The plate can wait.)

The first figure is the horticultural conservationist, philanthropist and all-around aesthetician Amy Goldman, who from her farm in New York’s Hudson Valley has championed the cause of saving heirloom varieties of vegetables. She did this as chairman of a national group named Seed Savers Exchange (she’s now an adviser) and as the author of three lavishly produced books that gave voice — and color images — to old and endangered varieties of squash, melons and tomatoes.

Her latest book, “Heirloom Harvest,” is out this week and takes her veggie crusade to another level. It is broader in scope and chronicles her restoration and improvement of the historic 210-acre farm. But the core of the book contains more than 100 plates of heirloom varieties, mostly of vegetables along with some fruits and nuts. If Goldman is the strategist of this project, its tactician — New York photographer Jerry Spagnoli — best captures its drama.

This is because Spagnoli works in the earliest popular photographic method, the daguerreotype: a cumbersome, fickle and messy process that produces some of the most arresting black-and-white images imaginable. The subjects have a volume and a polish to them but are also bathed in shadow. This chiaroscuro lends them a quality that is both ghostly and tangible.

“This technique has not been surpassed in terms of that palpability,” Goldman said.

Goldman included the Tennessee Cut Short beans in the book as a nod to her husband Cary Fowler, who grew up in Memphis. Fowler led efforts to establish the Svalbard Global Seed Vault in Arctic Norway. (Jerry Spagnoli/Bloomsbury)

Goldman is a leading figure in the movement to protect genetically diverse heirloom varieties that otherwise might be lost. This is an okra variety named Clemson Spineless. (Jerry Spagnoli/Bloomsbury)

Thus, the sheepnose pimento pepper resembles a spaceship of waxed mahogany floating in the ether; the D’Alger melon is like a primal beast in its cave. These have been converted to paper stock, but to examine the daguerreotype itself heightens the subject’s essence.

Spagnoli offers an explanation: “You subliminally feel the reflection of the mirrored surface,” he said. “You don’t see the image as being on the surface of the mirror, but behind the mirror. There’s a sense of reality and transparency that other photographic media don’t have.” This is why, when you look at a 19th-century daguerreotype, “the person is in some way physically present in the plate.” Creepy, but cool.

There is a reason this early photography was eclipsed soon by other technology, and not just because of its reliance upon poisonous mercury vapors. It is a ridiculously laborious venture.

Spagnoli takes a 61/2-inch-by-41/2-inch copper plate coated in silver and polishes the surface to a high gloss. The plate is sensitized with the vapors of iodine and then bromine in an enclosed box, transferred to the camera, exposed, returned to the vapor chamber to be cleaned of the light-sensitive salts, toned with gold chloride, and then sealed behind glass to protect the image and prevent the silver from tarnishing. There is no negative or paper print.

Even with the help of 19th-century manuals, there was much that Spagnoli had to perfect through trial and error, from heating the plates to caring for the polishing materials. “It’s very elemental, but the craft is all about finesse and very subtle things,” he said. Inventor Louis Daguerre was no longer around to guide him.

At the start, Goldman would harvest selected produce and drive it from her farm in Rhinebeck, N.Y., to Spagnoli’s Chelsea studio. It was there she observed Spagnoli at work and came to see him not so much as a photographer but an alchemist.

“To watch him behind this black curtain and with these vapors. . . . He emerged like the Wizard of Oz,” she said.

About three years into the project, they realized that these studio shots had limitations. It took Spagnoli as long as three hours to expose an image, and he discovered that even the most robust root vegetable would not hold up. Eventually, he set up a studio in the barn at the farm, where he would use a view camera to photograph vegetables that Goldman would deliver on her rounds. The large-format film negative was converted to a positive, which was then turned into a daguerreotype back in his studio. This let him capture a honeybee in flight or Indian Runner ducklings — subjects that would appear as just a blur on a direct daguerreotype.

Toward the end of the project, the one company that made the film positives folded. At that point, Spagnoli used a digital camera as the image source for the daguerreotypes, bringing the history of photography full circle.

Goldman sees the poignancy of using antique imagery to capture antique plants. Heirloom varieties grow true from seed, are at least 50 years old and often embody narratives of an otherwise forgotten agrarian past.

Armenian cucumber. All the vegetable and fruit subjects in the photography book “Heirloom Harvest” were grown at Amy Goldman’s historic farm in the Hudson Valley. (Jerry Spagnoli/Bloomsbury)

Many were in danger of being lost until the rise of the seed-saving movement in the 1970s, and the implicit message in all of Goldman’s work is that the biodiversity encoded in these plants offers an alternative to industrialized agriculture with its hybrids and genetically modified crops.

“Heirloom Harvest” takes cherished heritage varieties and elevates them further as individuals, which of course is the opposite of the mass production of farm crops.

White currants. (Jerry Spagnoli/Bloomsbury)

The book also contains echoes of the work of a mysterious English gardener named Charles Jones, who in the years before World War I took studio portraits of vegetables, as well as fruits and flowers. Unpublished and almost lost, they were saved by a collector and photo historian Sean Sexton and published in 1998 as “Plant Kingdoms: The Photographs of Charles Jones.”

Jones used a later photographic technique than Spagnoli did, with glass negatives and gelatin silver prints, but a soulfulness redolent of daguerreotypes shines through. A squat onion glows with a metallic sheen. Pods are cracked open to reveal rows of peas like black pearls. Five Savoy cabbage heads form a finely textured pyramid.

“He was a genius,” Spagnoli said. “There’s a kind of transparency that some people can achieve between the medium and their own inner life. There’s something about Jones’s work that shows a passion for the photographs and the subject matter.”

Last fall, Spagnoli and Goldman stacked newly gathered Moneymaker tomatoes on a plate and took the last image. It was a conscious nod to Jones, a fellow traveler in the spare terrain of vegetable portraiture.

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