Bella, I was at a local needlework shop yesterday and the girl there was working on a pillow covering that she'd embroidered with all sorts of different fiber threads and naturally dyed brown. Some of the fibers and the base linen fabric were very light, nearly tan, but the silk threads were nearly Black, they'd taken the dye so well. I just wanted to let you know so you can go slow with the walnut when you do your dye batches. I'm not sure if you can rinse out some of the dye to lighten if afterwards if it gets too dark too quickly.
It was such a nice piece . Now I can't wait to see what you do with your finished product!