Men are forbidden to wear clothes that are dyed with saffron.
`Abd Allah b. `Umar said: “The Prophet peace be upon him saw me wearing two garments dyed with saffron, so he said: “These are the clothes of the unbelievers, so do not wear them.” [Sahîh Muslim (2077)]
The Prophet (peace be upon him) also forbade `Alî from wearing clothes dyed with saffron. [Sahîh Muslim (2078)]
Though saffron is a plant that grows in Arab lands, there is a disagreement about the trace that it eaves on the clothes from saffron whether it is closer to yellow or red.
In any event, it is authentically established that the Prophet (peace be upon him) wore both yellow and red garments.
Ibn `Umar was asked about the things that he liked to do. One of the things he mentioned was dyeing clothes with yellow dye. He said: “I have seen the Prophet (peace be upon him) dyeing clothes yellow, so I like to do so as well.” [Sahîh al-Bukhârî (376) and Sahîh Muslim (503)]
As for wearing red garments, Abû Juhayfah related that he saw the Prophet (peace be upon him) walking in a red garment, with its sleeves pulled up. [Sahîh al-Bukhârî (376) and Sahîh Muslim (503)]
Al-Barâ’ b. `Azib also narrates that he saw the Prophet (peace be upon him) in red clothes. [Sahîh al-Bukhârî (3551) and Sahîh Muslim (2337)]
With reference to saffron, however, we also have what is narrated by Ibn `Umar that used to dye his clothes with saffron and use it as an ointment. When asked why, he replied by saying: “I saw it to be the most preferred dye of the Prophet (peace be upon him) and he used to use it as an ointment and as a dye for his clothes.” [Sunan Abû Dâwûd (1772)]
The scholars have disagreed in how to reconcile between the hadîth that indicate the prohibition of dyeing clothing with saffron and the hadîth that permit it.
The strongest opinion is the one mentioned by al-Tirmidhî when he related a weak hadîth about the prohibition of wearing red. He said: “Its meaning is understood by the people of hadîth to be that he (the Prophet, peace be upon him) disliked clothes dyed with saffron, but that clothing dyed red with other dyes is permissible as long as it is not dyed with saffron.”
On the basis of this understanding, it is permissible to wear yellow and red garments.
Ibn al-Qayyim understood that the red color garments worn by the Prophet (peace be upon him) were not pure red, but that they had red stripes. He considered it to be better to avoid pure red garments.
Red or yellow garments which are dyed with saffron should be avoided if it is known that saffron dye was used, in consideration of the hadîth mentioned earlier.
The justification for this ruling might be simply to avoid emulating the unbelievers who dye their clothes with saffron.
It should be noted that this is now quite rare to find garments dyed with saffron and most dyeing materials now are made of petroleum and chemical products.
In short, it is permissible to wear any garments which are either known to be dyed with other than saffron or which are dyed with an unidentified dye.
And Allah knows best.