Picking takes place during flowering (July-August), when the flower heads are almost faded.
The flowers are washed 4 or 5 times with water to remove unwanted material (yellow dyes) and then pressed and dried in the form of cakes for sale.
To extract the dye, the flowers are placed in contact with an alkaline solution (soda or straw ashes) for one hour and must be filtered to obtain the carthamine extract.
The residue is treated again with lye until exhaustion.
To precipitate carthamine as a powder, a weak acid (made from green plums or acetic acid) is used. Color can be dried for preservation.
Dyeing of papers is performed in two ways: pulp dyeing (sukizome) or sheet dyeing (hitashizome by dipping or hikizome by brushing).
To dye paper by soaking, the sheets are plucked one by one between two wooden sticks by their small side. This will keep the sheet flat during soaking.
Usually the pulp is dyed in the vat before forming the sheets.