A:
What the silos subtract, which is 5%, is the due Zakah on wheat.
As for the price of the wheat, farmers should start counting a new Hawl from the date they receive it. Thus, after the passing of a Hawl and if the money reaches the Nisab (the minimum amount on which Zakah is due) from the time of receipt, Zakah becomes due on it. The amount of the due Zakah is 2.5%.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.