INDIGO HISTORICAL DYE RECIPES

How To Dye With Woad & Indigo – Historical Dye Recipes
Indigo Fermentation Vat (With Bran & Washing Soda)

German Vat. […] Having filled the copper with water, we are to heat it to 200°Fah.; we then add 20 pailsful bran, 22 lbs. of carbonate of soda, 11lbs. of indigo, and 5 1/2 lbs. of lime, thoroughly slaked, in powder. The mixture is to be well stirred, and then set aside for two hours; the workman should continually watch the progress of the fermentation, moderating it more or less by means of lime or carbonate of soda, so as to render the vat in a working state at the end of twelve, fifteen, or, at the most, eighteen hours.’ (A Manual of the Art of Dyeing, 1853)

From this – I notice that a fermentation vat can be working within 12 – 18 hours!

Indigo Woad Fermentation Vat (With Yeast)
‘The woad or pastel vat according to Homassel. – To set this vat, it is useful to employ either putrid water, or an old vat of madder, to accelerate the fermentation of the woad;

but if you have not these, proceed thus: The day before you set your vat, grind twelve or fifteen pounds of woad, and having put it in a basket, pour hot water upon it to moisten it. Let it thus remain till it comes down to the warmth of leaven. Then take four ounces of yeast, and mix it with warm water, add it to the pastel or woad and stir it in; cover it so that it may retain its heat. In a short time the fermentation begins, and the woad becomes of a fine green colour; this serves as a ferment or leaven for the vat. After this, common water will answer the purpose, which when boiled for a short time is emptied into the vat, but the woad must not be put in while boiling, otherwise it will set, and be injured.

And yeast can be used to ferment the vat.
Also I am assuming that the same methods will work for Indigo as well.

More About Indigo

Coloriasto – The Practice of Dyeing Blue

Notes Upon Indigo
” The attractiveness and utility of the largest class of these fabrics are due to the hue given them by the dyer; and of all the coloring materials one of the most precious is indigo. In former times, as it still does at the East, it occupied with madder the place of one of the two most important of all dyeing materials. Forced of late years to give way to the marvellous products of modern chemistry, it will doubtless resume its place under the influence of a more enlightened economy and a more subdued taste. To contribute to the hastening of this return is one object of this essay. The most usual reproach against American fabrics is the want of stability in our dyes,—a reproach without justice, if applied to American fabrics alone; for the cheapening of dyestuffs is practised in all the so-called manufacturing nations, and is contemned alone in the East, from which we have derived our arts, and by the people whom we despise as barbarous. To remove this reproach from American fabrics would be worthy of no little temporary sacrifice on the part of our manufacturers.

The value of indigo as a dyeing material is due to the great stability of the blue color, and the derivatives from blue, which it gives to fabrics, especially of wool and cotton. It is not sufficient that a dyed fabric should preserve its color when 4 submitted to violent tests, as when acted upon by vegetable or mineral acids or alkaline or soapy baths: the only stable dyes are those which resist air and light, the two destructive agents of vegetable colors. Indigo, from the remarkable manner in which its color becomes fixed upon a fabric, to be hereafter explained, possesses properties of resistance and stability in a higher degree than any blue dye. And when we consider that this blue has not only its own hue, but is the best foundation for blacks, greens, purples, and even browns, the importance of these properties cannot be over-estimated. “
By John L. Hayes, 1873