Sayyidah Umm Layla (may Allah be pleased with her) narrates: "We gave our pledge of allegiance to the Messenger of Allah (peace and blessings be upon him), and among the things he (peace and blessings be upon him) took a pledge from us on was that we should apply henna dye fully by dipping (the hands), that we should comb our hair with honey, and that we should not leave our hands bare and dry of dye (henna)."
Hadith Referenceالمعجم الأوسط / باب الميم / 8054
Hadith Takhrij«أخرجه الطبراني فى «الكبير» برقم: 334»