This week for Flora and Fauna Friday is a lanky legume with a pigment pedigree, Carolina Indigo (Indigofera caroliniana).
Carolina Indigo is a small, airy shrub found on dry sandy ridges between the pines of savannas and along oak-hickory wood-lines. It often gets about chest high with wiry burgundy stems lined by small scarce leaves and covered with fine, sparse hair. The plants love bare sandy soil below dappled sunlight and so often find themselves at home in fire prone pine savannas. Much like Coralbean, Carolina Indigo dies back to its roots every winter only to reemerge the following spring. Plants bloom in June and July with slender spires of tiny peach-colored pea flowers. Seed pods are minuscule and contain only one or two seeds.
Carolina Indigo is one of three species of true Indigo that were cultivated for dye in the colonial United States. However unlike its tropical cousins, Guatemalan Indigo (I. suffruticosa) and True Indigo (I. tinctoria), Carolina Indigo was never a major cash crop. Indigo crops were grown for pigment that could be rendered from their leaves. Fresh leaves and stems were harvested, fermented in vats of water, strained, agitated, and mixed with lime from baked oyster shells to produce a deep blue dye that was then dried, cut, packaged, and sold. Indigo experienced only a brief period of profitability in South Carolina before the Revolutionary War. Guatemalan Indigo was believed to have been the species of choice on South Carolina plantations. Yet, Carolina Indigo saw some limited use as a dye early on in history as well as minor use for individual domestic dye production. Carolina Indigo never took hold for two reasons: the dye it produced was paler and it had low yield of dye per acre due to a biology that differed considerable from its imported cousins. Unlike the tropical Guatemalan Indigo which yielded dense leafy growth and grew feverishly until first frost shut it down, Carolina Indigo had adapted to the temperate climate and some of the harshest growing conditions South Carolina had to offer. This meant it grew slow, had fewer branches with less leaves, and spent more time building a robust root system to survive droughts and fires. Without any competitive commercial utility, Carolina Indigo quickly faded back to obscurity where it quietly grows along our roadsides and woodlots to this day.
