Anas b. Malik (Allah be pleased with him) reported that Allah's Messenger (ﷺ) forbade the sale of fruits until these are mellow. They (the companions of Anas) said:What is meant by" mellow"? He said: It implies that these became red. He said: When Allah hinders the growth of fruits, (then) what for the wealth of your brother would become permissible for you?

English translation · Sahih Muslim