Tuesday, May 8, 2018

woad 2017

A brief word about indigo containing plants first. In my studies I have learned that indigo blue can be isolated from at least three different plants: woad (Isatis tinctoria), "bagdad" indigo (Indigofera tinctoria), and Japanese Indigo (Persicaria tinctoria/Polygonum tinctorum). The first time I tried Indigofera tinctoria I only got two plants to germinate at all and they yielded no blue. The same year, 2015, I grew Isatis tinctoria and yielded a little success but only sufficient florey in my vat to paint out one circle of blue that I evidently didn't take pictures of. 2016 was the summer we moved. There were no extant gardens on the property and not enough energy to install them until 2017.

In 2017 I grew woad, Isatis tinctoria, in three large red planters in the front garden at the new house in Windham. I was more careful to feed the plants well in 2017. Two of the pots were only "50/50" mix from the garden center who said "It's really about 70/30 loam and Benson's. Any richer would burn your plants." And the third pot included amazing compost from an acquaintance of my mom who makes it with kitchen scraps and mess from his chicken coop.


As before I planted them in 'shallow drills'. I planted them on May 17th 2017, knowing that I could lug them inside if frost threatened. Usually I would wait in Maine for May 31st to avoid the dangers of frost.




In 2017 I fed them every month with Plantone and watered as the weather demanded.

This was the pot planted in a mix of the loam/bensons and the lovely fluffy compost mix I mentioned. These plants did especially well.

On October 18th, 2017 I cut the leaves off of the plants, noting their number. The pots without fluffy compost yielded numerically more plants but they were notably less lush. The dry leaves en masse weighed 721g. I'm thinking that the rumor I've read about the water running off woad leaves causing germination inhibition must be true. The water running off healthier plants, growing in a medium they preferred may have caused a number of the seeds to not germinate... That would have left more root room for the healthiest to absorb more nutrients and be lush and healthy plants. It's too bad that I combined the leaves from the two soil tests rather than independent baths but I felt if I didn't I would not get the amount of blue yield that I wanted.

For the extraction I used the washing soda/soda ash/sodium carbonate method this go like this website. I washed the leaves twice in Rerverse Osmosis (RO) filtered water whose pH measured 7.

After washing I stripped the leaves off of the stems and manually tore them into smaller pieces, observing and noting "woad smells funny and had little caterpillars living on it" in my notebook.
an example of the inch worms on the woad
Then the cut leaves were dumped in hot RO water. After bringing it back up to 80oC (176F) quickly, I took it off the burner, covered it with a lid and steeped the leaves for 10 minutes.

After steeping I cold water and ice bathed the whole pot and quickly cooled it to 55o C/131F. I poured the leaves and liquid through a colander into a bucket, squeezing the leaves with gloved hands to   encourage the release of every last drop of dark brown/red potential indigo containing liquid. Then back into the stockpot it went with a Tablespoon full of Arm and Hammer Washing soda dissolved in a mug full of hot RO water, cooled past the recommended 50oC(122F) to 118F, turning it greeny-brown.

Then I aerated the heck out of the vat using a stainless steel immersion blender, turning it blue!

Collecting masses of these bubbles in glass bowls elated me!  Yay florey! Indigo! Blue! My very own pretty scum from dyer's vats that I can call 'flower'! I shall call it flower even if it doesn't smell like one... ;)

I can't comfortably wear most wool. I'm here for the blue flower from the vat so it's good that I like growing things and didn't find this disheartening note from Broecke's Il Libro Dell'Arte until after successfully making some blue.
Indigo chemically identical to that imported from India was produced throughout Europe in the period from woad, and this was used as a cheaper alternative to imported indigo for dyeing wool blue. However, the yield from woad was too low to make it suitable as a source of dyes for less absorbent yarns or of pigments and inks (Broecke 41)
It's a good thing this is only a hobby! ;P

But later she thinks 'woad' is intended as a modifier for azurite (Broecke 86). So who can be certain?

In Medieval Painters' Materials and Techniques The Montpellier Liber diversarum arcium translation by Mark Clarke, there is a recipe that elaborates a process:
1.3.35 Another preparation of azure. On how to make azure, and that which will be better than that which is extracted from mines: take very white marble, and roast it in a gentle fire for a day and a night; which, after it will be roasted, grind extremely finely on another [slab of] very hard marble, and then take the scum of indigo-- which is on the cauldron of dyers in which is made indigo color--from the water; saturate the aforesaid marble powder, and grind strongly on the aforesaid marble [slab], and when it will be dry, repeatedly saturate it, for a long time, until it has the fine colour of azure; then remove it from the [grinding-] stone and put it aside, and use for work.
(Clarke 2: 105)
I'm excited to make some of this blue but first I need a new smaller muller and marble powder. Stay tuned for this blue and more! The flower of the woad definitely yielded some blue pigment when it dried! It still smells funny to me but evidently that's a perpetual problem with woad even if you don't use the extraction methods with urine.

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