We recently held a dyepot "workshop" aka puttering around with dyes at a re-enactors crafting weekend.
Only a fraction of natural dyes were available in northern Europe during the medieval period. The most common dyes were weld (yellow), madder (red and orange), and woad (blue). Some other dyes were available, such as walnut (brown and black), kermes (scarlet and super expensive), cutch (browns), and brazilwood (reds, imported from Asia).
Before the weekend, the dyestuffs were extracted.
Black walnuts were harvested from a neighbors yard (they begged us to take more). These were soaked in water for several days and then simmered for several hours. This extract gave a light brown color in cool tones. A better result was gained from then allowing the hulls to sit in a bucket for several more days, then smashing them and re-simmering. Smelly!
Walnuts on the stove:
The best result with madder root came from soaking the madder for several days, roughly chopping the root and putting it in a blender with some water, then simmering and extracting about three baths.
Madder extraction bath:
I only had dried weld. Soaking the weld and extracting once (hot, not simmering) with chalk in the bath gave only very pale color. I then allowed the weld to soak until it started to ferment (several days) and was able to extract two batches of stronger color. The second bath became more tan than the first. A much brighter yellow was brought out by putting the fabric into an after bath with some ammonia.
The cutch came in a powdered form and was simply extracted in a single simmering bath. Brazilwood was soaked and extracted once, but it can be extracted several times.
Setup: borrowed propane crab cooker and my Big Pot. Extra buckets, chemicals, electronic scale. This was sooooo much easier to work with than trying to use the Big Pot on a tiny electric burner or on a stove. It holds at least 10 gallons of water with room to spare.
I premordanted most of my fabric and roving with alum. A few pieces were mordanted in the pot.
The Big Pot was able to hold 2-3 yards of fabric, some yarn, and roving. Each bath was held at a near simmer for 1-1.5 hours.
The weld bath was first
Then walnut was added to the weld bath to conserve water (water was taken from a rain barrel and was in limited supply). The walnut bath was then dumped and a new bath was started with madder. When the madder seemed to be exhausted, brazilwood was added to the same bath. Then a second batch of walnut was added to this bath.
Items dyed with walnut, madder, and brazilwood.
The cutch bath was done later. I also re-extracted and dyed one of the walnut fabrics, the weld fabric, and madder fabric.
Left to right,
~1 oz cutch on 11 oz wool gabardine.
Single bath walnut on 14 oz shetland wool
re-extracted walnut on 11 oz wool gabardine
re-extracted madder (4 oz) on 14 oz shetland wool
fermented and extracted weld (500 g) on 11 oz wool gabardine, first extraction after fermenting. A second piece of 11 oz wool gabardine was dyed to a similar depth of color but with a more tan tint with the second extraction after fermenting.