Mukhtasar Bukhari

Narrated from Sayyiduna Abdullah bin Umar (may Allah be pleased with them both) that the Messenger of Allah (peace and blessings of Allah be upon him) forbade selling fruits until their ripeness becomes apparent, and (forbade) selling dates on the tree in exchange for dried dates. Then he said that Sayyiduna Zaid bin Thabit (may Allah be pleased with him) informed me that the Noble Prophet (peace and blessings of Allah be upon him) later permitted the sale of ‘Ariyyah (dates on the trees) in exchange for fresh or dried dates, and did not permit it in any other case. (The meaning of ‘Ariyyah is that the fruit of a tree is given as charity to a poor person, then if his coming to the orchard causes inconvenience, the fruit of that tree is bought back from him by estimation.)