For a few years now, I’ve been either harvesting dye plants from the wild, or ordering them online. But this year was the inaugural year of my own dye garden. I dedicated one raised bed to plants that yield blue color: woad and Japanese indigo. The woad, sadly, got overtaken by the neighboring, overenthusiastic ground cherries during the weeks when I was out of town… but the Japanese indigo grew very well, and I ended up with a good harvest of its leaves. I spent a late summer afternoon extracting the dye, holding my breath till I got to the last step of the process: would it work?
It totally did.
I must say that growing the dye yourself takes the incredible satisfaction of giving fibers magical new colors to a whole new level. To be able to look at that sweet blue color and say, “I grew that!” …
Dyeing with Japanese indigo (and woad, for which the process is quite similar) is also a relatively sustainable choice. The fibers don’t need to be mordanted, which means no potentially hazardous metals in waste water. Secondly, neither the plant material nor the fibers need to be boiled at high temperatures, so the process requires less fuel/energy than most other kinds of dyeing.
Japanese indigo seeds can be hard to find. I got mine here.
1. Harvest Japanese indigo at the height of summer, when a leaf turns blue if bruised. Remove leaves and put them into large jars or other heatproof container with a lid. Cover the leaves with warm water and place inside of a larger pot, also filled with water, so that the water in the pot partially covers the jar. Heat water to 160-170 F and keep it at that temperature for 2-3 hours. Do not overheat!
2. Strain the dye liquid into a bowl and squeeze liquid out of the leaves as well. Discard the leaves. Pre-wet your fibers in the warm water that’s already in your pot.
3. Add baking soda (a tablespoon per a pound of Japanese indigo).
4. Pour dye liquid from one bowl to another to oxidize it for about 8-10 minutes. Then add a tablespoon of Spectralite and wait until the liquid turns yellowish green.
5. Carefully submerge your fibers for 10 minutes or longer.
6. Carefully remove the fibers and marvel as they turn from yellow-green to blue when they come into contact with air.