Sayyiduna Jabir bin Abdullah (may Allah be pleased with them both) says that the Messenger of Allah (peace and blessings be upon him) forbade selling fruits until they ripen. It was asked: What is "tushaqqih"? He (peace and blessings be upon him) said: "Fruit that turns red and yellow and is eaten from."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب البيوع / 10600