Vera Stewart wrote: One of the things I wonder, especially as you say it grows with little care, is whether or not it's likely to "go rogue" and try to colonize neighbour's yards?
To sum up: Woad balls can be used in the same way as fresh woad leaves, except that the leaves should remain in the vat throughout. Whisking may not produce any blue froth but ignore this & continue as usual. The vat itself will not look like the more usual woad or indigo vats, but this does not seem to be of any importance. The vat can be kept going over several days & the colours from this type of woad vat will be more green in tone.
It is warm enough to sow woad seeds in the UK when daffodils are in flower.
Historically speaking, woad indigo was always extracted through a long and laborious fermentation process. ...
...woad leaves are first harvested, and then ground up on a giant woad mill. ...
When the woad leaves were crushed, they were piled in small heaps to drain. Once the woad was dry enough to be cohesive the piles were pulled apart and formed into woad balls. The woad balls were anywhere from two to six inches in diameter. These woad balls were then dried in specially constructed drying racks, exposed to air movement but shaded, to prepare for storage. Dried woad balls could be stored indefinitely before couching.
"Dyer's Woad" - Isatis tinctoria
Kingdom - Plants - Plantae
Division - Flowering Plants - Anthophyta
Class - Dicots - Dicotyledoneae
Order - Mustards/Capers - Capparales
Family - Mustards - Brassicaceae
Species - Dyer's Woad - Isatis tinctoria
Professor Philip John from Reading University who had been doing some interesting microbiological research on the mediaeval fermentation vat used in a re-enactment at Chiltern Open-Air Museum by John Edmonds. They described a new species of Clostridium bacterium (C. isatidis) which was responsible for chemically reducing indigo in fermentation dyeing vats, based on a mediaeval recipe.
Vera Stewart wrote:I have ordered some woad seeds!
Do you have any experience growing it in large pots? I'm wondering if it would be "safer" in terms of trying to avoid introducing an unwanted invasive to my neighbourhood by accident if I grew a couple of plants in large pots...but perhaps the roots are too big/strong?
Vera Stewart wrote:Aplogies if you've already said somewhere in this thread - how long did it take for your woad sprouts to start coming up? I planted my seeds in trays March 25th and I don't see anything coming up yet.
Here are some indicators that you’re ready to take leaves out. Big emphasis on “Some” because you may not see all of these signs or they may differ slightly so don’t think of this as a checklist...
•The liquid in the vat has turned from clear to a yellowish bluegreen 'antifreeze' color
•There are bubbles forming on the surface
•There are blue pigment particles floating on the surface
•There's a coppery/oily looking sheen on the surface
•Most of the leaves have a slightly slimy film on them or the leaves have turned from bright green to yellow and look “spent”.
• you can also try the lime test with a small clear, lidded jar. Add liquid and a drop of lime and shake vigoriously for a few minutes, you should see blue pigment start to float.
r ranson wrote:Sounds a lot like the start of a fermentation vat. Were they adding anything else to it before or after?
This post details a form of aqueous alkali precipitation extraction starting from fresh Japanese Indigo aka Persicaria Tinctorium(any indigo bearing plant can be used, keeping in mind certain varieties of indigo contain more indican than others.) Fresh leaves are soaked in water, an alkali solution is added, aerated, settled, and strained to achieve a dry indigo powder pigment or paste. The pigment can then be stored and used in various Indigo reduction vat recipes.
Will the liquor get hot enough to extract the dye?
Another very effective way to aerate is by dipping a plant pot (of the type with holes in the bottom) in the saucepan (fig. 10). Lift it above the saucepan and let the liquid drip through the holes in the bottom of the plant pot, back into the saucepan. Using the plant pot is fun and less tiring on the arms than using a hand whisk.
Judith Browning wrote:I know you're not interested in using facebook but there are some interesting groups there discussing natural dyes. One is devoted to indigo vats and covers woad also...another I am learning a lot from has to do with lichens and mushroom dyeing and the third is natural dye ferments.
All three have active real time problem solving discussions and are quite helpful.....natural dye nerds!!!