The English word saffron comes from the Arabic sa’faran and is used as the name of the plant Corous sativus and for a bright orange/yellow color the same as or similar to the color derived from the stigmas of this plant.
Saffron was unknown to the Buddha’s India, growing only in Persia at that time. The Pali/Sanskrit word for saffron, kunkuma, does not occur anywhere in the Pali Tipitaka. Saffron was imported into northern India in later centuries but never used to dye cloth. It was used in medicine, to flavor and color food but it has never been used as a fabric dye because it washes out after the third or fourth wash. A further reason why it has never been used to dye monks’ robes or any other cloth is its expense. In Singapore today an ounce of saffron sells for a little less than an ounce of gold. It was even more expensive in ancient times. City monks in Thailand often wear robes that could well be described as saffron-colored although safety-helmet orange would be a more accurate description. But just as many monks and especially forest monks wear robes of a soft brown color. Monks’ robes in Burma are uniformly purple/brown and in Sri Lankan they range from Communist Party red to dark brown. If Tibetan monks’ robes were to be given a botanical association it would have to be beetroot. So how has saffron come to be so associated with Buddhist monk’s robes?