Recently there was a thread on one of the fiber lists on using pokeberries as a dye, and on whether or not pokeberry colors fade. My response was basically that it depends on how acetic the dye bath was. Following that, I received personal requests for more clarification and actual recipes. Feeling this may be of general interest, we've added the recipe here.
There are so many surprizes with pokeberry. I've been experimenting with it for 18 years. I even prepared an interesting University research project as part of my masters program, taking berries from three different soils, and using three different water sources, and premordanting in various mineral salts, to try to determine various effects on the color. (Why would copper turn the color to buff yellow? Why do the mineral salts seem to "cause" the color to fade?) Still many unanswered questions.
Pokeberry colors range from bright fushia to magenta to raspberry, and will last for several years by following the below recipe. Three factors seem to greatly effect the color and color retention: the concentration of dyestuff to fiber, and the degree of acidity of the mordant and dye baths, and the length of time fibers remain in each step of the process.
I don't take accurate measurements when dyeing with native plants, but I'll estimate for you. The proportion of dyestuff to fiber is critical. I find the higher the ratio of pokeberries to fibers, the more color-fast. I never weigh pokeberries, so don't know what a bucket of pokeberries weighs, but would estimate one-to-two gallons of berries (off the stems and crushed) to 8 ounces of fiber would be good. Try 4 oz. of 56% acetic acid to enough water to comfortably float the fibers (about 1.5 to 2 gallons). Thoroughly wash and rinse the fibers, while damp enter fibers into acid water, bring to a high simmer (180-190 degrees F) for two hours and leave over night to cool in bath. Meanwhile add acid water to the crushed pokeberries, steep for 30 minutes (don't get temp too high or you may loose the brilliant red), then let cool overnight. Next day strain the seeds from the dyebath. Remove the fibers from acid ath. Combine the dyebath and the left over acid bath and put the fibers back in. Then cook at a medium high temp (160-180 degree F) for two hours. Leave fibers in bath for several hours or over night. Remove fibers, squeeze and lay out on screens in shade for couple hours to oxydize. Then thoroughly rinse off excess dye (do not use soap or anything alkaline) and dry.
Over-dyeing skeins and raw silk fabric in indigo, once the pokeberry is set, will give purples (surprise, as indigo is alkaline!) Once I dyed a skeing of wool first in pokeberries, then in indigo, for one of the most beautiful purples I'd ever seen. Then, being very tired, and very much a pokeberry-dyeing novice, left the skein in a bowl of warm water and Dawn dishwashing liquid overnight! The next morning the skein had turned sage green!! Another time I dyed locks of wool first in pokeberries (with weaker vinegar) then in indigo, and after rinsing, had the most unusual colors on each lock. The alkaline of the indigo seemed to effect only part of the pokeberry dye. There was red, blue, green and purple, all on the same locks of wool! I'm sure the way the cut end and tip ends of locks takes dyes differently, had a lot to do with the variations! While doing two-day historic dye demonstrations, I always noted that the pokeberry colors, even WITH postmordant mineral salts, hich were left in the dye baths overnight were always darker and more color-fast than colors allowed in the bath for only the usual hour or so.
However, the best color, and color retention, was discovered toward the end of a dye workshop with author and dye master Jim Lyles at the Campbell Folk School in 1995. A fellow student, Jeri Forkner, and I couldn't resist picking buckets of pokeberries after dark on the evening before the last day of class. We set up the dye baths late at night, and, having run out of vinegar, dumped in some 56% acetic acid and left the dye bath, and fibers in the mordant bath, overnight. The bright magenta colors on the wool skeins and raw silk fabric samples were impressive, even to Dr. Lyles. And to this day, years later, there's no sign of fading, whereas a similar skein, mordanted in vinegar only, is showing signs of yellowing.
Pokeberry is my favorite dye plant. My favorite color. A graceful shrub. And we EAT the tender poke leaves/stalk when it first comes up in the spring. Tastes JUST like asparagus!! It took a couple years to convince my husband not to remove every pokeberry volunteer sprouting up in our back yard. But now, we encourage every one-- even in our vegetable garden. They always surround our compost pile (where the seeds are dumped following workshops.) It is such an honored plant, we use it as part of our company logo. Hope you learn to enjoy it as much as I.