Yahya related to me from Malik from Humayd at-Tawil from Anas ibnMalik that the Messenger of Allah, may Allah bless him and grant himpeace, forbade selling fruit until it had become mellow. He was asked,"Messenger ofAllah! What do you mean by become mellow?" He said, "Whenit becomes rosy."The Messenger of Allah, may Allah bless himand grant him peace, added, "Allah may prevent the fruit frommaturing, so how can you take payment from your brother for it."
USC-MSA web (English) reference: Book 31, Hadith 11
Arabic reference: Book 31, Hadith 1303