Dyes from Dock seed heads

Just a quick photo here to show the colours I obtained from the pre-soaked seed heads of the broad leaf dock plant, Rumex obtusifolius. For several weeks I kept checking the plants (which grow wild in our garden) to see when the seeds would be ready. I was keen to try using the seed heads after reading in Su Grierson's book "The Colour Cauldron" (self published, 1979 reprint, now out of print) that a red dye could be obtained if the seed heads were given regular heating over a few days. She obtained apricot / caramel shades and first and thought this red was coming through because of decomposition of the dyestuff. I think I should have used more plant material to get a stronger colour.

I didn't get to the brick red she described, but in the sample on the left of this picture you can see a more pink/red tone coming through. This wool sample was dyed three days after the others, with approx 3 hours heating of the dye bath in total before dyeing. Next springtime I shall try again, as I am told that the young spring leaves also give reds.

The samples to the right are, far right, with after mordant tin (stannous chloride), centre with after mordant iron (ferrous sulphate) and then both the samples on the left are only treated, as all this wool was, my usual pre-mordant of 10% alum (potassium aluminium sulphate) and 8% cream of tartar (potassium hydrogen tartrate). The wool is superwashed merino, again.