Over the last few months, my Invasive Pigments project has yielded a wider variety of colors than I might have guessed when I began. Fruits, leaves, stems, and roots gathered mostly from plants growing here in Bushwick have produced rich browns, pale oranges, reds and yellows, deep purples, and of course a range of greens.

Looking at the typical artists’ color wheel, it’s easy to pick out the missing pigment: blue. As described on a recent Radio Lab episode, blue pigmentation is fairly rare in nature. I had already intuited this by looking at my own color swatches and by reading about humanity’s long running obsession with the creation of a blue rose.

Above: The transgenic blue rose created by Japanese and Australian researchers in 2005. (It still looks purple to me! ) Image credit: Koichi Kamoshida.
The Radio Lab episode explored the rareness of blue through a different lens: the evolution of language. Historically, many cultures had no word to describe it. Homer’s Iliad and Odyssey, originating around 800 B.C., refer to a range of colors by name, with red and black being most common, followed by fewer mentions of other colors. Blue is entirely absent. It seems that the culture in which Homer lived may not have had a need for a word with which to name the color blue.
As described by linguist and writer Guy Deutscher, this pattern is fairly common across cultures. In many languages, words for black and white appear first, followed by red, yellow, and green. Blue is almost always added last. One hypothetical explanation for this pattern has to do with a culture’s ability to “reliably produce blue”. Due to the scarcity of naturally occurring blue pigments, blue dyes and paints have also been rare for much of human history. The need to select something blue, and thus name it, is reduced. I’ve simplified things a bit here; check out the podcast for a more detailed summary of Deutscher’s thoughts on this, as well as some interesting takes on another obvious blue presence in our lives: the sky.
Naturally, I’ve been interested in the possibility of remedying this lack of blue in my Invasive Pigment palette.

A few weeks ago, I came across a crop of asiatic dayflower growing along the edges of Linden Hill Cemetery in Ridgewood, Queens. The plant’s tiny flowers, each of which blooms for only a day, are emphatically, unmistakeably (at least to my eyes) blue.

Discovering a blue blossom does not necessarily mean that processing it will result in blue pigment. Bright green paulownia leaves have given me my richest, darkest brown, and pink lady’s thumb blossoms yield a pale purplish-gray. Even so, I was cautiously optimistic as I walked the edges of the cemetery, plucking blossoms where they sprawled outside the fence and sprouted from cracks in the pavement. Back in the studio, I separated the blue petals from the yellow and maroon stamens and pollen.
Next, I piled the petals into my mortar, added a drop of gum arabic and ground them into a paste. I was delighted to find that the petals broke down into a deep azure that spread across my mortar and pestle in streaks. After straining and mulling, the new pigment mixture still maintained its color, so I set it aside to cure, fingers crossed. When I returned to the studio the next day, I tested it and found that even a single layer from a wet brush produced a lovely pale blue:

Since then, I’ve been researching the evolution and migration of asiatic dayflower, and have discovered some interesting history: in its native range it was once used as a pigment for coloring woodblock prints and dying paper. Japanese Ukiyo-e prints of the 18th and 19th century are believed to contain pigment from the dayflower variety Commelina communis var. hortensis, which was cultivated widely before it was replaced by synthetic Prussian blue.

Above: Ukiyo-e woodcut by Suzuki Harunobu. According to Wikipedia, the “the blue pigment used on the kimono is believed to be aigami made from petals of the Asiatic dayflower…”
In addition to its beautiful pigment, asiatic dayflower has another remarkable quality: it seems to be one of a handful of naturally glyphosate resistant plants. Glyphosate, the active ingredient in Roundup, has been added to agricultural fields in increasing volumes since the advent of Roundup Ready corn and soybean crops in the mid 90s. Pressure on weed populations in agricultural settings has revealed a subset of plants that have pre-existing or newly evolved tolerance for glyphosate-based pesticides. Have you seen the stories of six foot high, combine breaking “superweeds”? Below, glyphosate resistant Palmer Amaranth on a study plot in Arkansas:

Glyphosate resistant plants have free reign in many corn and soybean fields because their other weed competitors have been poisoned out of existence. Paralleling the development of antibiotic resistant bacteria, glyphosate treatment of Roundup Ready fields selects for stronger and more resistant weeds with each generation. After a little research, it seems that in addition to being considered invasive by many states, my little blue flower is well on its way to becoming a “superweed”.
Below, a dayflower blooming in my studio:
