The Black Walnut tree is native to North America. One such tree grows on the edge of my neighbor's pasture. Another grows in a vacant lot next door to my son's home. I have been fortunate to be able to harvest walnuts from both trees. While the nut is noted for its flavor, the green hull of the nut can be used for dyeing. When ripe, the nuts fall from the tree, the green hull loosens from the nut and can be easily peeled off.
My first exploration in dyeing with walnut hulls was autumn of 2009 when the hulls were freshly picked up from the ground. Peeling the hulls from the nut, I put them in the dye-pot, covered with water, and let simmer for about an hour, then let it cool down. The liquid was a deep brown. After soaking in tap water for about 20 minutes, I immersed the yarn in the dye-pot and allowed it to simmer for about an hour.
|Wool yarn, Black Walnuts|
|Black Walnut sample mordant card|
The local fiber guild was having a meeting, so I gathered up my dye stuff and loaded the dye pot with the walnut liquor in the back of my truck. I had a couple of skeins of mink yarn I had purchased the month before at a fiber retreat. The mink yarn happened to be white...probably bleached to remove the natural color, and I thought it would be beautiful a deep espresso brown! I would throw the mink, as well as a skein of recycled cashmere, a skein of my hand-spun merino/baby alpaca/angora, and a handful of alpaca fiber into the dye-pot. A fiber friend had brought some mohair yarn and fleece, as well as some angora to add to the pot. None of our fibers had been pre-mordanted. The walnut hulls are rich in tannin and no mordant is necessary for the color to stay. However, using mordants can shift the color to slightly different shades.
We soaked our fibers in tap water for about 20 minutes prior to putting them in the dye-bath. Then we brought the temperature to a simmer and allowed the fiber to simmer for almost two hours.
While in the pot, the fibers appeared to have taken on that dark espresso brown we wanted, but we were surprised to see that when we pulled the fiber from the pot and squeezed the liquid out, the fibers were still only a medium-light brown. The mink and wool were a taupe shade, while the mohair was taupe with a reddish hue. The angora was a light shade of gray. The dye bath was still rich with that deep espresso brown, so I don't believe we had put too much fiber in for the amount of dye matter. Perhaps the difference in color,from what I had achieved in 2009, was due to the fact that these hulls were not used fresh. I had also put one of my mordant sample cards in the dye-bath and that gave us a good indication of what other shades of brown we might achieve using mordants.
|Mink on left, recycled cashmere center right, mohair on right.|
|Mohair fiber after 1st time in walnut dye-bath.|
|Angora fiber after 1st time in walnut dye-bath.|
|Black Walnut sample mordant card - 2014|
Seeing the sample mordant card, we all agreed that the dark brown with the iron mordant was stunning! There was still plenty, PLENTY of color in the dye-bath but we had run out of time for the day. I would take it up tomorrow, re-dye these fibers using some iron mordant and see if we could get a deeper shade of brown.
Next day: I divided the dye into two pots, setting one aside and adding 1/4 tsp. of iron salts to the other. The mohair, angora, and alpaca fiber went into this one and simmered for about 2 more hours. The addition of the iron definitely gave us a deeper shade of brown on the mohair and alpaca, and a darker gray on the angora. I decided to go ahead and add 1/4 tsp. of iron to the other half of the dye liquor and simmer the skeins in that pot.
Here were the final results:
|Black Walnut dyeing - 2014|
Note: comparing the results from 2009 using the fresh hulls and 2014 using hulls that had soaked in a pail of water all winter, it appears that using the fresh hulls will yeild darker browns.
|Comparison of fresh hull dyeing to hulls that had soaked all winter.|