Woad, wonderful woad... growing and dyeing

So, the harvest has yielded!
This was my first year growing woad, and look at the lovely colour I got for my urine/ woad hot box combo ( see older posts for using this method ).
As blue is such a difficult natural dye colour to get, I decided to grow some this year from seed. I also know exactly where they came from (really local!) and there were no petrol transport miles involved in this process at all! I was donated the seed via a friend's mother, but also bought some on line.
One of the wonderful things about woad, is that you can harvest it in the first year of growth, in fact you need to, to get lovely blues, so the results are as quick as they can be!
I started growing these woad plants in February, as they really seem to need some frosty cold to germinate properly. Some seeds were sown directly into the ground, some were started off in little pots in my back yard. By the time it came to harvesting them ( any time from late August ), there was no difference in the size of either group of these plants, so either method is fine, but ofcourse, planting them in the ground first means , perhaps, one less process togo through ( although maybe more weeding?). Almost all the seeds germinated (hooray!), and a few leaves were a little munched here and there. In the end I had about 35 plants to harvest. One of them flowered, although woad is generally bienial in the UK (perhaps because some ants had decided to nest under it...). This plant is yet to bear fruit, so maybe might not this season, but an older plant I was donated has done, and I've harvested the black pendulous seeds from it, so hopefully can get a crop next year too.
It is the lovely lush green leaves you harvest, at a point in the year when they've had plenty of sun! Although this summer seemed very rainy, it was also rather sunny, and the proof is in this lovely blue I've obtained.
These leaves were harvested at the beginning of September, and brewed for two weeks in the warm urine vat. My harvest from the plants at this point was 1700 grams of leaves, and I used half of them for this brew, and reserved half of the dye liquid in (hopefully) airtight containers, for later use. This amount yielded about 300 grams of dyed fibres (mostly wool), from pale sky blues  (one dip, or when the vat was running out) to a rather dark blue (from as many as 4 dips).
The green in the picture was a lovely yellow from birch leaves on a young jacobs wool fibres, that I overdyed with one dip in the woad vat.
Wenslydale locks came out a more royal blue than the blue faced leicester and shetland wool fibres. The really deep jeans blue was on soya silk fibres, but bamboo fibres came out much paler ( top left hand corner, on second photo). I also dyed some naturally grey  and moorit shetland wool fibres: the blue only started to show after 3/4 dips, but I do like the effect too ( very top L hand corner, photo 2).
A month later, and I might be able to sneak one more harvest out of these plants before the cold darkness means they won't yield any more blue. If all turns out well, that might mean about 900 grams of fibres dyed from 35 plants.. We'll see how the saved dye liquid works out...

Finally, some photos of the lovely plants prior to harvest, they are about 6 inches in diameter...
 And woad in flower, not to be harvested for blues apparently!

Hot Box Natural Woad Dyeing

So, woad, what a fantastic quirky gift from Mother Nature...A leaf that yeilds a beautiful blue, but only if you hit upon the right alchemy...

This is my most recent method, involving that most maligned (because of the stink) of all waste products, WEE.
So first of all, fill a vessel with wee, let it sit, somewhere where it won't be disturbed or fiddled with for a least two weeks, until it stinks. You want the smell to make you gag when it gets you in the back of the throat. Then (if you're using powdered woad) add 2 teaspoons to approx 5 litres of gone off urine. With leaves, you just want to fill up your heatable vat (I use a big stainless steel pan) with as many leaves as you can and then pour the urine over them.
Then the method is the same: heat your vat with woad in to just slightly steaming point then PUT IT INTO YOUR PREPARED HOT BOX! This is the marvelous part of it for me, as I had to think it up myself!

I couldn't work out how I could keep my woad vat at a steady temperature, perhaps for several weeks, as I had no greenhouse, and our stove is never on constantly, as our house is too cosy, and doesn't need constant heating, even in the depths of winter. Then I remembered the hot box principle: Basically, heat whatever you need to keep at a constant temperature up to the temp you want it to be at, take it off the heat source, and then insulate it so that the heat stays in it. In my case, the most easily available insulation source was fleece (My house is literally full of the stuff). So I put a layer of it ( 2-3 inches)on the bottoms and sides of an old cardboard box, then placed the heated pots (in my case) with the woad urine vats in the hot box (see photo above) added a cosy wool covering to the pots, and shut the box up. I discovered that this will stay warm for approx 24 hrs, and then you just heat it up again to slightly steaming point, and put it back in the hot box again. Probably after 3-4 days the woad will have dispersed enough and the vats' oxygen reduced enough for you to begin dyeing. You should be able to tell because the vat will look greenish. If there is a blue scum floating on the surface you may need to add more gone off urine. I keep my wool fibre in for 24 hours to absorb the vat fully, and then I air it by pulling it carefully out of the vat on a stick and watching it magically turn blue in the Air! If it's too pale, I repeat the process and usually after 3 or 4 days it's a lovely mid blue. See above photo.
The important thing is too keep your vat at a steady temperature, although too cold is more easy to rescue than too hot, which can give you greys and maroons rather than the magical blue you are after.
I rinse my woad dyed wool in luke warm vinegar water to help it bond to the fibre. Then air it until I wash the smell fully out! The smell will always lingre a little, but generally only when the fibre is wet....
 You can top up your vat every few days with urine until the woad is worn out. If you have more woad, you can keep it going for weeks, but your family may not be impressed with the smell of you heating up the vat everyday on the stove.....