Freshly harvested blocks of indigo pigment at Okan Arts Farm

indigo: blue gold

By Patricia Belyea

WAUCONDA WA  Here’s the gist of my story: I grew a crop of indigo plants and extracted indigo pigment from their bright green leaves. To follow are the details.

Spring

Wanting to get a good start on my indigo crop, in early March I soaked the teeny black seeds in water overnight. I used a pair of tweezers to plant the indigo seeds into 10X20 cell packs. Then I pampered them with heating pads and long hours under grow lights.    

My enthusiasm and care produced seedlings that grew and grew. By mid-May, my seedlings were good-sized plants. Every morning I carried them outside to enjoy the sunshine and every evening I brought them inside to avoid any late Spring frosts.  

Living in the Okanogan Highlands, I couldn’t risk planting my tropical indigo in the ground until mid-June. But the mass of plant matter and pots was becoming overwhelming with over 200 plants in our kitchen each night.

I built a simple hoop house with PVC pipes and a sheet of plastic so the plants could stay outside. On the coldest nights, a greenhouse heater warmed the air under the plastic tunnel.

Soaking the indigo seedsIndigo seedlings at Okan Arts FarmHoop house to protect the fledgling indigo plants at Okan Arts FarmIndigo plants inside the hoop house at Okan Arts Farm

June 14: Planting Day

Loading the plants into the wagon, the indigo plants and I headed down to our fenced field. Most of the plants were skinny and root-bound in 4.5” round pots; a few were huge, in 1 gallon and 2.5 gallon pots.

It took two days to plant all the indigo, one foot apart, in the prepared 65’ rows.

Patricia Belyea takes the indigo starts to the field for planting at Okan Arts FarmPlanting indigo at Okan Arts FarmFreshly planted indigo at Okan Arts Farm

Summer

Although our area experienced a drought this year, the indigo plants flourished with regular irrigation from our deep well and long days of sunshine. On some Sundays, they were treated to earthworm casting tea.

By the end of summer, all the indigo plants had burgeoned in size—making happy hedges that were 3 feet high and 3 feet wide.

Indigo growing at Okan Arts Farm, Wauconda WA

Early Fall

Over half the crop was harvested for the magical indigo dye and the rest was left to go to seed.

Early one morning about 130 plants were cut close to the ground. The plant matter was loaded into the wagon and driven up to the house. 

Harvest indigo plants at Okan Arts Farm in Wauconda WAHarvesting indigo at Okan Arts FarmHarvesting indigo at Okan Arts Farm

Immediately the branches, with their bright green leaves, were submerged in three big tubs of warm water and weighed down with garden tiles on wire mesh.

As the indigo leaves began to ferment, a smell permeated the air. It was an organic, bright aroma—the smell of blue!

After two days of soaking, an oily rainbow film appeared on the surface of the water. The indigo plants were removed. Their spent leaves were now army green.

Fermenting indigo plants at Okan Arts Farm in Wauconda WAFermenting indigo at Okan Arts Farm in Wauconda WAFermenting indigo at Okan Arts Farm in Wauconda WAProcessing indigo pigment at Okan Arts Farm in Wauconda WAProcessing indigo pigment at Okan Arts Farm in Wauconda WA

Using hydrated lime, the pH of the water was raised to 11. Bubble stones, like those used in aquariums, agitated the green-blue water for about one hour. 

Then it was time to wait.

The next day, the water color had changed to a golden brown and the bottom of the tubs were covered with deep blue particles—indigo dye!

Processing indigo pigment at Okan Arts Farm in Wauconda WAProcessing indigo pigment at Okan Arts Farm in Wauconda WAProcessing indigo pigment at Okan Arts Farm in Wauconda WA

Most of the water was carefully decanted from each tub using a battery-operated fuel pump. The very last of the water and the precipitated blue particles were tipped into a silk bag placed in a 5-gallon bucket, drilled with big holes, over a bin.

First the silk bag was squeezed to release as much water as possible. Then it was hung from the rafters overnight to continue to drain.

Processing indigo pigment at Okan Arts Farm in Wauconda WAProcessing indigo pigment at Okan Arts Farm in Wauconda WAProcessing indigo pigment at Okan Arts Farm in Wauconda WA

The next day, a deep blue mud was scooped out of the bag and spread into a square baking dish. (Three batches were made.) Once most of the water was evaporated, the indigo cake was scored and cut into little blocks.

Success! Our 130 plants yielded over five pounds of indigo pigment!

Processing indigo pigment at Okan Arts Farm in Wauconda WAProcessing indigo pigment at Okan Arts Farm in Wauconda WA

What’s Next?

I have three things on my mind:

1. I have to ensure that the magenta blossoms on the remaining plants turn into black pods bursting with seeds. This means covering the plants with frost blankets on the nights that threaten to dip below freezing.

2. I have to learn how to make an indigo vat. I certainly have enough dye to try many times.

3. I’m interested in playing with shibori dyeing. There’s lots for me to learn about Japanese tie-dyeing and clamp-dyeing techniques.

Indigo blossoms at Okan Arts Farm in Wauconda WA

I’ve actually dyed hundreds of yards of yukata cotton with natural indigo at the Botanical Colors private dyeing studio. But those indigo vats were prepared for me.

So now I need to figure everything out on my own. My friends, Mr. Google and Ms. YouTube, plus the folks in the Indigo Pigment Extraction Methods Group on Facebook, will be great resources. (And maybe I'll make a lifeline call to Kathy Hattori at Botanical Colors.) 

Onward!

To visit Botanical Colors to purchase natural indigo dye +click here

Below are yukata cottons that Victoria and I over-dyed with natural indigo at the Botanical Colors private dyeing studio in June 2019. 


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