Sunan Ibn Majah, Book 12, Hadith 2294 (In-Book) ⓘ

It was narrated from Ibn 'Umar that the Messenger of Allah said: "Whoever buys a palm tree that has been pollinated, its fruits belong to the seller, unless the purchaser stipulated a condition." (Sahih) Another chain from Ibn 'Umar, from the Prophet, with similar wording.

حَدَّثَنَا هِشَامُ بْنُ عَمَّارٍ، حَدَّثَنَا مَالِكُ بْنُ أَنَسٍ، قَالَ حَدَّثَنِي نَافِعٌ، عَنِ ابْنِ عُمَرَ، أَنَّ النَّبِيَّ ـ صلى الله عليه وسلم ـ قَالَ ‏ "‏ مَنِ اشْتَرَى نَخْلاً قَدْ أُبِّرَتْ فَثَمَرَتُهَا لِلْبَائِعِ إِلاَّ أَنْ يَشْتَرِطَ الْمُبْتَاعُ ‏" ‏ ‏.‏