Murasaki is also known as purple or red gromwell or red root lithospermum or zicao in Chinese……jichi in Korean or murasaki in Japanese.
The dye compound in the roots is shikonin which is somewhat similar to the more widely used dye compound in alkannin from dyer’s alkanet.
Seeds take a little longer to germinate. Leave at least 2 weeks for germination and the soil should be kept moist during and after germination. Plant outdoors after danger of frost or start in potting soil. I often have had poor germination with many things I seed directly in the ground, even with attentiveness, and this has caused me great frustration, but this plant did germinate for me well in the ground, and I was very attentive to watering.
I actually seeded this plant in less than the best soil initially, because it was all I had available at the time, and the plant did grow. The site had some shade as well and was near black walnut trees that produce a juglone toxin that inhibits growth in plants that are sensitive to it. The plants did grow and showed themselves hardy in my zone 6b but did not thrive as well as they could have. When I was finally able to dig up more garden beds farther from walnut trees, I moved some of the murasaki plants into better soil and more sun and they thrived and grew bushy, whereas they were merely surviving ok in the poorer soil which I initially had them.
Plant the plants in nice loose, good soil because you want the roots to grow big and strong, because that is what you want to harvest for dye. You can use the roots either dried or fresh for dye. Second or 3rd year roots are best since they’ve had some time to grow and get thicker. Otherwise you’ll notice quite a lot of thin spidery roots. To extract the lavender dye, first rinse the dirt off the roots and then massage the roots in water for half an hour or more.
I rinsed 2 year roots in water so they were free of dirt. Most of the roots were thin with a few larger roots, and I tried using them fresh. I massaged the roots in cool water for a little while and then added my already alum mordanted superwash wool yarn. The color of the water was brick red. I was getting a light lavender on my yarn but then I remembered reading about using alcohol to help extract more color. The dye in this root is similar to the dye compound found in alkanet root that you have to use alcohol to extract, so I thought it couldn’t hurt. Well, I wish I hadn’t added rubbing alcohol to the water! The color of the water turned more orange brick color than burgundy brick color and now it only imparted a tan on my yarn! So I suggest NOT using alcohol!
I have not been able to find current information on dyeing with Murasaki, other than what I’ve shared here. It is not widely used in the U.S. right now. I want to experiment more this year.
The dried roots have been used as a Chinese herbal medicine and the dye made from murasaki roots was put under sumptuary laws during the Heian period and restricted murasaki-dyed clothing to the Empress and her ladies in waiting.
If you are ever unhappy with seed or any other product you receive from me, please let me know. Especially with seed, I feel that if the seed should not produce well, the waste of the growing season is the biggest shame and a refund unfortunately cannot make up for that loss of time.