Why Indigo?

    By Geoffrey von Maltzahn

    We here at Indigo have been getting this question a lot over the past few weeks. As a company dedicated to harnessing nature to help feed the planet, some are curious about how “Indigo” aligns with our mission.

    In fact, Indigofera, the crop genus from which indigo is derived, has a rich agricultural history - one that embodies our ambitious goals and values as we strive to help improve farming and our foods. This history resonated with us, and elements of our own research also pointed us to the name. We’ll get to that, but first, what exactly is indigo?

    Indigo is a legume with symbiotic nitrogen-fixing bacteria in structures called root nodules. Legumes need little or no nitrogen fertilizer in order to provide high yields for the grower, and play a key role in crop rotation, which helps reduce soil erosion, and improve crop yield. This relationship between nitrogen-fixing bacteria and plants is a hallmark example of plant microbiome benefits, and also the tip of the iceberg.

    Of course, indigo is most well known as a natural blue dye - a special and rare color in biology - in textiles, derived mostly from two of the over 300 species of the Indigofera genus: Indigofera tinctoria (native to India and Asia) and Indigofera suffruticosa (native to South and Central America). It was used in ancient Asia and Europe to stain clothes and textiles, by the Aztecs to darken their hair and the Mayans to produce azure paint for works of art.

    It holds a special place in U.S. history as well, as one of the first agricultural crops grown in this country. By the American Revolution, domestically produced Indigo was such a commodity that it was known as “Blue Gold.” Growers had discovered that small cubes of indigo were more profitable and easier to ship and defend than bulky bags of rice. Cubes could be used in place of paper currency (valued at roughly $2 per pound), and made up 35% of all exports to England.

    During our process of studying plant microbiomes across hundreds of plant species and over 40,000 endosymbionts, we learned quite a bit about the interactions taking place within plants. At the core of our discoveries was the realization that the plant microbiome can greatly shape a plant’s biology and protect them from an array of stresses, including drought, heat, salt, cold, nutrient deficiencies, insects and microbial pathogens.

    One of the more fun observations we made was that some of a plant’s pigments can be modified, produced and influenced by more than just the plant’s biology. Specifically, certain plant microbes could help create the color indigo. This happened when we observed that certain microbes can produce Indican, a colorless compound which releases glucose and indoxyl that, when oxidized, creates the color indigo. Other plant microbes could oxidize indican to reveal the color directly, revealing bright blue colonies of plant microbes in our labs.

    This observation that a common plant pigment can be influenced by the plant microbiome is thematic of our broader story—that the plant microbiome plays extraordinary roles in the biology we’d previously associated with plants.

    Also, just as blue is a rare color in biology, we have a special opportunity of our own: to be a leader of a new kind of agriculture - one that is both increasingly natural and scalable. We’re striving to be the first ag tech company to serve the needs of both farmers and consumers and to increase yield and grower profitability while making vital, sustainable changes to how our food is grown. We look forward to sharing more about our science, our team and our vision for better agriculture with you.