Coreopsis & Marigold (Solar + Iron + Exhausts 2 & 3)

Last year I grew and harvested coreopsis and marigold flowers, and earlier this year I solar dyed some handkerchiefs with the dried flowers and alum. I reported on the vibrant results in Dye Project: Coreopsis & Marigold (Solar + Alum). It was surprising how much color was produced with so few flowers. I loved the bright yellow from the marigold and the deep orange from the coreopsis. At the end of the post I expressed an interest in reusing the dye baths in a second exhaust, using Ferrous sulfate as the mordant. I ended up doing a third exhaust as well. This follow-up post reports on the surprising results!

Exhaust 1 after three weeks

Exhaust 1 - marigold on the left, coreopsis on the right

Exhaust 2

I reused the dye and the plant material from Exhaust 1. To each jar I added a few inches of fresh water and 1/4 teaspoon (26 grams) of Ferrous sulfate, and stirred until well mixed. I added two cotton handkerchiefs and wool yarn in layers with the original plant material. I poured in the reused dye (Exhaust 2) and topped it off with water as needed. I left this batch in the sun for six weeks, agitating the jars daily to distribute the dye evenly.

Salvaging dye and plant material for Exhaust 2

Preparing iron mordant for Exhaust 2

Exhaust 2 dye with iron mordant

The dye bath deepened in color over the course of three weeks (it was surprising how much color remained). After six weeks I treated the fabric as usual: rinsing until the water ran clear; hanging to dry; washing with a pH neutral soap after two weeks; and then hanging to dry again.

Exhaust 2 + iron after six weeks

Exhaust 2 + iron hanging to dry

The resulting color was lighter, as you would expect from a second exhaust, and the color was duller with the iron mordant.

Marigold comparison: Exhaust 1 + alum on left; Exhaust 2 + iron on right

Coreopsis comparison: Exhaust 1 + alum on left; Exhaust 2 + iron on right

Exhaust 3

I decided to see what would happen if I reused the dye and plant material from Exhaust 2. This would be Exhaust 3 of the dye bath, with little hope of results, but I decided "why not"? The coreopsis dye bath had only a remnant of color, and the plant material was basically black with no orange pigment. But the marigold dye bath still had color, and the plant material had quite a bit of color. I repeated the same steps used for Exhaust 2, but this time used cotton fabric instead of handkerchiefs; and left the jars in the sun for eight weeks instead of six, thinking more time might pull out any last remnant of color.

Exhaust 3 + iron after eight weeks (on an overcast day)

Exhaust 3 + iron: the marigold has a surprising amount of color

Exhaust 3 + iron: the coreopsis color is gone, so the iron dyes a grayish color

Exhaust 3 + iron + solar comparison: Marigold on the left; Coreopsis on the right

Color Comparison

For fun, look at the range of shades produced with marigold and coreopsis flowers, solar dyeing over multiple exhausts, and with alum and iron as mordant brighteners!

Marigold and Coreopsis: shades of color produced