I was in the garden, pulling out the tomato plants and putting the stakes away for the winter when I noticed my paltry little patch of Woad had finally started growing. With the summer drought, it didn't grow much at all and I really didn't want to risk our well by watering the garden too much. When I planted it, there was a row of regular Woad and a row of Chinese Woad, hoping to do experiments to see what the differences were between the two Woad varieties. However, this year, there wasn't enough of either to do two decent dye vats, especially this late in the season, when sometimes the pigment isn't as strong as in the heat of the summer.
I grabbed a pot and combined the two types of Woad, picking almost every leaf I could find, in hopes of having enough blue to make this dye vat worth while. I even picked the few Dyer's Knotweed leaves there were, knowing that it needs a slightly different processing to get the full value of the pigment it contains. I was hopeful that it would add at least a little indigotin to the vat. There were about 700 grams of Woad leaves to work with.
I use a fairly standard method for processing Woad leaves, similar to what is found in many dyeing manuals available today. I soak the leaves in water which is very hot - I boil the kettle, turn it off and when it stops bubbling, I pour it over the leaves. It took 2 kettles full of water to cover the leaves. Then I let the leaves sit for about an hour. I used to be precise about waiting 40 minutes but have found that approximately an hour is as good and much less worry. After squeezing out all the liquid from the soaked leaves, I use baking soda (sodium bicarbonate) to make the solution alkaline. The liquid then needs to be aerated, which I used to do by pouring back and forth between two buckets. These days though, I use my craft stick blender, which is fast and easy. The liquid is supposed to be a sherry colour, but mine was a dark icky brown. The aeration causes foam. Usually I've had a white foam and when the pigment starts to develop, you see it as blue specks on the foam. However this foam was light brown and I never did get any flecks, although finally in a weird shadow, I saw a faint blue cast to the foam. I picked up the stick blender to stretch for a minute and noticed that it was stained a much darker blue than before. I decided that the pigment was there but the brown froth was masking it. Two spoons of Thiox to start reducing the vat, and poof, I knew I didn't have too much too worry about. The only question would be how much blue was in the pot?