Sunan At-Tirmidhi
Hadith #1228
Narrated Anas: ""The Messenger of Allah (ﷺ) prohibited selling grapes until they appear and selling grains until they become firm."" [Abu 'Eisa said:] This Hadith is Hasan Gharib, we do not know of it being Marfu' except from the narration of Hammad bin Salamah