It is narrated from Sayyiduna Ibn Umar (may Allah be pleased with them both) that the Noble Prophet (peace and blessings be upon him) said: "Whoever sells a tree in which date palms have been grafted, then its fruit will belong to the seller, unless the buyer stipulates otherwise."
Hadith Referenceمسند احمد / مسند المكثرين من الصحابة / 4552