Ibn 'Umar (Allah be pleased with them) reported that Messenger of Allah ﷺ forbade the sale of palm-trees (i. e. their trults) until the dates began to ripen, and ears of corn until they were white and were safe from blight. He forbade the seller and the buyer.

أَنَّ رَسُولَ اللَّهِ ﷺ نَهَى عَنْ بَيْعِ النَّخْلِ حَتَّى يَزْهُوَ وَعَنِ السُّنْبُلِ حَتَّى يَبْيَضَّ وَيَأْمَنَ الْعَاهَةَ نَهَى الْبَائِعَ وَالْمُشْتَرِيَ