Blue is the high concentration of 100-year-olds in Zones in Greece, Japan, and Italy. Blue is the ‘Indigo River’ in China, as it is colloquially known, the part of Pearl River that connects to the Xintang township, and suffers run-off from the 200 million plus pairs of jeans produced annually.

Blue (1994) is Derek Jarman's last film. A blue screen with audio, as Jarman was going blind, due to AIDS-related complications, and blue was the last colour he could see. (There are ‘blue movies’, and there is Blue, the movie.)

Since 2004 Suntory has been trying to genetically engineer a blue rose. Yes, Suntory, the same Japanese company that produces Strong Zero, an alcoholic drink that had me singing karaoke from 8pm until the first train the next day when I was a teacher in Tokyo. The best ‘blue’ rose they have managed is, at most generous, lilac. They used a gene from a pansy to produce a ‘blue’ pigment in the rose petals.

In Celtic folklore it is said that if a wreath of bluebells flowers is worn, one can only speak the truth. Imagine the medical emergencies that would occur in the Beehive if this became uniform regulation.

Blue is the room installation artwork Yves Klein created in 1957 creating an immersive monochromatic blue environment. The entire space, including the walls, ceiling, floor, and furniture, was completely painted in his distinctive blue hue, which he patented as International Klein Blue (IKB).

Blue works by Lucio Fontana and Yves Klein, displayed at Sotheby's in 2020. Photo / Getty Images

A 2009 study by Juliet Zhu (et al., University of British Columbia) tasked 600 participants with cognitive tests that either called for an analytic or creative approach. They completed them on screens with red, blue, or white backgrounds. Red screens bettered performance on tasks that called for precision, e.g. detecting mistakes; and the blue screens generated higher success in creative tasks, e.g. brainstorming. Zhu concluded that red makes one think more meticulously. Blue, though, encourages innovation.

Wallace J. Nichols, a marine biologist, mirrors this in his book Blue Mind. He characterises the blue mind as how one feels when in, on, under, or near water – happier, healthier, creative and more connected. He contrasts this to the red mind which is overstimulated and chronically online.

Nichols states that water is a shortcut to a blue mind. He stresses that it does not need to be an ocean or a river, it can be domesticated water like a bath or a shower. It all makes perfect sense; we all spent around nine months full-time under water.

Blue is Augustus J. Pleasonton's magnum opus – his concept of The Blue Secret. Pleasonton (1808-1894) was so struck by blue that he built a glasshouse using only blue panes of glass and solemnly swore that the plants and animals he kept and grew inside of it were of superior quality. He was sure that something divine had whispered to him a secret that he must share: everyone should replace their bedroom window panes with blue glass. He printed the book on blue paper. Many listened.

Blue is the cyanotype, a photographic process which came onto the scene in 1842, just three years after the invention of photography. Only one year later, in 1843, British photographer and botanist Anna Atkins (1799-1871), self-published what is widely accepted as the first photobook; her cyanotypes of seaweeds titled Photographs of British Algae: Cyanotype Impressions.

Fucus vesiculosus cyanotype by Anna Atkins. Photo / The New York Public Library Digital Collections

Then, 133 years later, Francesca Woodman (1958-1981) appears to offer a nod to Atkins in a photograph from 1976, which shows Woodman collecting as much seaweed in her dress as she could carry. A subsequent series of images shows Woodman, now in her studio, laying collected specimens on a roll of white paper, which I interpret as another hat-tip to Atkins’ seaweed and other botanical collected treasures placed on the cyanotyped page.

In another nod Francesca Woodman, who was known for her small-scale black-and-white photographs, created Blueprint for a Temple (1980) a large scale blue diazotype piece comprised of 29 photographs (some of them over two metres tall) which were projected onto photosensitised paper and then developed with photographic chemicals. She produced this work shortly before her death at just 22 – a departure, in Woodman’s work and life – these last blued self portraits bruised into the paper.

Blue is a secret, a truth, a portal, a bruise, a temple, but, it is not a rose. Not yet.