Cold-Water, Fresh-Leaf Indigo Vat Dyeing
four shades of indigo from a cold -ater, fresh-leaf indigo vat
Let’s take a look at using fresh-leaf indigo in vat form. I’d like to begin with the various shades of robin’s-egg blue, now that you have had a chance to try your hand at direct contact with indigo leaves in Fresh-Leaf Indigo, It’s Magic!
We’ll take a beginner’s look at the most basic form of indigo vat – one made simply from fresh leaves and cold water. I’ll be using the Japanese tadeai indigo, but other varieties will work well, too.
Eggs of the mapuche chicken – Who wouldn’t love these colors?
John harvesting tadeai just after sunup
The yardage has been sewn together at the ends to create a loop. Using a set of dowels to help hold a portion of the fabric above the vat, John is picking up and pulling the fabric toward himself as the silk cycles through the dye below.
Just after sunrise, on a cool mid-summer morning, use a scythe to gather a small basket full of fresh leaves. Choose plants that look healthy and are deepest in color, preferably ones that aren’t yet in bloom.
Add the leaves to a blender with ice water and churn until the leaves are thoroughly pulverized. Strain. The resulting liquid is your vat and you are ready to go! This particular vat works best with protein-based fibers, so primarily silks and wools.
Wash your material thoroughly and rinse in cold water. The longer you soak the material, the richer the robin’s-egg blue. Whether you are using yarns or woven yardage you will want to keep the fiber moving for the most evenly colored results. You may simply swish the material periodically, or you may suspend it from rods and continuously turn it. Whether it is a books-on-tape thriller, or simply the neighbors going at it again next door, make sure you have something prepared to occupy your mind since this will take up to an hour or more for a deep color color to develop.
straining the pulverized tadeai leaves through a polyester rag, cookie brittle is optional
clamp resist on silk leno in fresh-leaf indigo vat
Remove the yarn or yardage from the vat, wring, rinse, dry, and you’re done. Since this vat is pH neutral, there is no need to subject the dyed fiber to a vinegar rinse. In contrast, many Japanese like to give it a dip in a slightly alkaline solution (1 teaspoon of calcium hydroxide dissolved 3 gallons of tepid water). However, this does have the potential to take the color just a bit to the indigo-gray side.
This method works wonderfully with resist techniques that can hold up to prolonged exposure to cold water, such as kasuri (ikat), rozome (batik), and itajime (clamp-resist) methods.
Three samples of fresh-leaf, tadeai vat indigo: fresh leaves with silk (left); fresh leaves on ramie with a little calx (calcium hydroxide) added to the vat (center); and fresh leaves and calx on cotton (right).
So, what about the cellulose fibers? Not to worry. We need only take the pH of the fresh-leaf vat from neutral to around 10.5 by adding dissolved calcium hydroxide (chalk) to a fresh vat and allowing the mixture to simply sit for about an hour. Repeat the steps you followed for the silk. You should wind up with a very beautiful blue –not quite as lively as the fresh-leaf dye on silk, but still a very refreshing turquoise.