Japanese Indigo Seeds
Japanese indigo (Polygonum tinctorium, also known as Persicaria tinctoria or dyer’s knotweed) is an annual plant whose seasons for planting are from spring to early summer which then grows through August and blooms in September-October.
It is a simple process to plant and grow indigo — all you need is, fertilizer, well-drained soil, full direct sun, and lots of water.
This packet includes:
- 10g of Polygonum Tinctorium seeds
- Instruction of planting and growing
This product can only be shipped in the US.
How to plant and grow Polygonum tinctorium:
Fill a plant pod with fertilized soil and make a hole in the middle with your finger about 1cm (or 1/2 inch) deep. Place 5-6 seeds and lightly cover the hole with soil. Give water and leave it under direct sunlight. It should start sprouting in 7-10 days. Make sure to water it thoroughly and keep the soil wet.
Once the seedlings grow over 4 inches high, you may transplant them to a more substantial planter or directly into the ground. Give a 6-8 inch distance to each seeding in a planter, or 8-12 inches the ground. Make sure to give them lots of water and sunlight. When fully grown the plants become about 2.5-3 feet in height and leaves become about 4-5 inches long. It is only the leaves that contain indigo pigments and can be used for fresh leaf dyeing.
The plants start blooming in September-October in which the tips of the plants produce a small pink flower bud where you will find seeds. At this point, the leaves no longer contain indigo pigments enough for dyeing. Therefore, to use them for dyeing, harvest them by the end of August. It should take approximately two months to fully mature for dyeing purposes, depending on which month you plant it is possible to harvest twice before the season is over. The plants will not survive the winter.