Shu'aib, form his father, that his grandfather said: “The Messenger of Allah only prescribed Zakat on these five things: wheat, barley, dates, raisins and corn.”
إِنَّمَا سَنَّ رَسُولُ اللَّهِ ﷺ الزَّكَاةَ فِي هَذِهِ الْخَمْسَةِ فِي الْحِنْطَةِ وَالشَّعِيرِ وَالتَّمْرِ وَالزَّبِيبِ وَالذُّرَةِ