Very plentiful in August is this lovely aromatic fennel. We decided to see what colors it would yield, and we had a (very) happy surprise.

This is the dye bath from one big fennel plant – the whole thing, except for the roots.

I took some cotton strips and pre-mordanted them in our homemade iron mordant. A month or so ago we put about 10 rusty iron nails in a mason jar with 2 parts water and 1 part vinegar, and left it out in the sun to “cure”.

Here is our dye bath split into 2: on the right is the iron-mordanted cotton, and the left is alum pre-mordanted cotton.

Though iron mordant often yields richer, deeper, even brighter colors, we found this did not happen with the fennel. The iron mordanted cotton gave us a metallic, light gray green. Above you can see it on the cotton, and a playsilk.

We left the alum pre-mordanted cotton in the fennel dye bath over night (soak only, no heat) and awoke to a beautiful yellow dye bath and colored cotton. Even after vigorous rinsing, the fennel’s yellow hue was stunning, we thought. Different than turmeric and golden rod – such a special yellow.

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