What did the Prophet Muhammad (saw) say about not buying or selling fruits before their benefit was evident?
      Narrated Ibn Shihab:                       If somebody bought fruits before their benefit      is evident and then the fruits were spoiled with blights, the loss      would be suffered by the owner (not the buyer).     Narrated Salim bin 'Abdullah from Ibn Umar:  Allah's Apostle said, "Do     not sell or buy fruits before their benefit was evident and do not      sell fresh fruits (dates) for dried dates."