حَدَّثَنَا مُعَلَّى بْنُ أَسَدٍ، حَدَّثَنَا وُهَيْبٌ، عَنْ أَيُّوبَ، عَنْ مُحَمَّدِ بْنِ سِيرِينَ، قَالَ سَأَلْتُ أَنَسًا أَخَضَبَ النَّبِيُّ صلى الله عليه وسلم قَالَ لَمْ يَبْلُغِ الشَّيْبَ إِلاَّ قَلِيلاً‏.‏
Translation
Narrated Thabit

Anas was asked whether the Prophet (ﷺ) used a a hair dye or not. He replied, "The Prophet (ﷺ) did not have enough grey hair to dye, (such that) if I wanted to count the fading hairs in his beard (I could have)."