Nowadays only 4 to 5 main families are still producing 'sukumo' in the traditional way. 'Sukumo' is the name given to 'ai' (indigo) leaves that have been prepared into a suitable condition for dyeing by fermentation, and which can be stored for more than a year. The basic procedure is the same among all the makers but each producer has his own particular twist on the process.

Kosoen uses sukumo provided by Mr. Nii in Kochi Prefecture. The pictures shown here are provided by the Nii family, and our story is based on an explanation from Mr. Murata the dyer, who visits them every year, and who also has experience with the procedure himself.


In spring the Nii family sows the fields with seeds of Japanese Ai (Polygonum Tinctorium). The timing of this seeding is critical; if it were to happen that there were a cold snap after some warm days, thus exposing the seedlings to cold early morning air, the entire year's harvest could be lost. They seed the latter half a few weeks later, to balance out the heavy work at harvest time by staggering the growing rhythms of the plants.



After about two months, the seedlings are replanted into large fields.

Hundreds of thousands of seedling are planted by hand.



The plants are growing well. The Nii family is busy at this time pulling weeds and hoeing the soil into ridges around the plants.

The ai plants are ready for harvest at the end of the rainy season.


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