I and Messenger of Allah ﷺ happened to pass by people near the date-palm trees. He (the Holy Prophet) said: What are these people doing? They said: They are grafting, i. e. they combine the male with the female (tree) and thus they yield more fruit. Thereupon Messenger of Allah ﷺ said: I do not find it to be of any use. The people were informed about it and they abandoned this practice. Messenger of Allah ﷺ (was later) on informed (that the yield had dwindled), whereupon he said: If there is any use of it, then they should do it, for it was just a personal opinion of mine, and do not go after my personal opinion; but when I say to you anything on behalf of Allah, then do accept it, for I do not attribute lie to Allah, the Exalted and Glorious.  

مَرَرْتُ مَعَ رَسُولِ اللَّهِ ﷺ بِقَوْمٍ عَلَى رُءُوسِ النَّخْلِ فَقَالَ مَا يَصْنَعُ هَؤُلاَءِ فَقَالُوا يُلَقِّحُونَهُ يَجْعَلُونَ الذَّكَرَ فِي الأُنْثَى فَيَلْقَحُ فَقَالَ رَسُولُ اللَّهِ ﷺ مَا أَظُنُّ يُغْنِي ذَلِكَ شَيْئًا قَالَ فَأُخْبِرُوا بِذَلِكَ فَتَرَكُوهُ فَأُخْبِرَ رَسُولُ اللَّهِ ﷺ بِذَلِكَ فَقَالَ إِنْ كَانَ يَنْفَعُهُمْ ذَلِكَ فَلْيَصْنَعُوهُ فَإِنِّي إِنَّمَا ظَنَنْتُ ظَنًّا فَلاَ تُؤَاخِذُونِي بِالظَّنِّ وَلَكِنْ إِذَا حَدَّثْتُكُمْ عَنِ اللَّهِ شَيْئًا فَخُذُوا بِهِ فَإِنِّي لَنْ أَكْذِبَ عَلَى اللَّهِ ﷻ  

The Messenger of Allah ﷺ passed by some people who were at the top of the palm trees. He said: ʿWhat are these people doing?ʿ They said: “They are pollinating (the trees), putting the male with the female.” He said: ʿI do not think this can help in any way.” They were told about that and they stopped doing it. News of that reached the Messenger of Allah ﷺ and he said: “If it will benefit them, then let them do it. It was only a passing thought. Do not blame me for a mere thought, but if I tell you anything about Allah (may He be glorified and exalted) then accept it from me, for I will never tell a lie about Allah.ʿ  

مَرَّ رَسُولُ اللهِ ﷺ عَلَى قَوْمٍ فِي رُءُوسِ النَّخْلِفَقَالَ مَا يَصْنَعُ هَؤُلاءِ؟ قَالُوا يُلَقِّحُونَهُ يَجْعَلُونَ الذَّكَرَ فِي الْأُنْثَى قَالَ مَا أَظُنُّ ذَلِكَ يُغْنِي شَيْئًا فَأُخْبِرُوا بِذَلِكَ فَتَرَكُوهُ فَأُخْبِرَ رَسُولُ اللهِ ﷺ فَقَالَ إِنْ كَانَ يَنْفَعُهُمْ فَلْيَصْنَعُوهُ فَإِنِّي إِنَّمَا ظَنَنْتُ ظَنًّا فَلا تُؤَاخِذُونِي بِالظَّنِّ وَلَكِنِ إذَا أَخْبَرْتُكُمْ عَنِ اللهِ ﷻ بِشَيْءٍ فَخُذُوهُ فَإِنِّي لَنِ أكْذِبَ عَلَى اللهِ شَيْئًا  

I was with the Prophet ﷺ and he passed by some palm trees of Madinah, and he saw some people at the top of the palm trees who were pollinating them. He said: “What are these people doing?ʿ [Talhah] said: “They are taking (pollen) from the male and putting it in the female, to fertilise it.” He said: ʿI do not think this can help in any way.” News of that reached them, so they stopped doing that and came down from the trees, which did not bear any fruit that year as a result. News of that reached the Prophet ﷺ and he said: “It was only a thought that crossed my mind. If it helps in any way, then do it. I am only human, just like you, and thoughts may be right or wrong. But if I tell you that Allah, May He be glorified and exalted, said something, I will never tell a lie about Allah, may He be glorified and exalted.” It was narrated from Moosa bin Talhah ( and he narrated a similar report.) a similar report  

مَرَرْتُ مَعَ النَّبِيِّ ﷺ فِي نَخْلِ الْمَدِينَةِ فَرَأَى أَقْوَامًا فِي رُءُوسِ النَّخْلِ يُلَقِّحُونَ النَّخْلَ فَقَالَ مَا يَصْنَعُ هَؤُلاءِ؟ قَالَ يَأْخُذُونَ مِنَ الذَّكَرِ فَيَجْعَلُونَهُ فِي الْأُنْثَى يُلَقِّحُونَ بِهِ فَقَالَ مَا أَظُنُّذَلِكَ يُغْنِي شَيْئًا فَبَلَغَهُمْ فَتَرَكُوهُ وَنَزَلُوا عَنْهَا فَلَمْ تَحْمِلْ تِلْكَ السَّنَةَ شَيْئًا فَبَلَغَ ذَلِكَ النَّبِيَّ ﷺ فَقَالَ إِنَّمَا هُوَ ظَنٌّ ظَنَنْتُهُ إِنْ كَانَ يُغْنِي شَيْئًا فَاصْنَعُوا فَإِنَّمَا أَنَا بَشَرٌ مِثْلُكُمْ وَالظَّنُّ يُخْطِئُ وَيُصِيبُ وَلَكِنْ مَا قُلْتُ لَكُمْ قَالَ اللهُ ﷻ فَلَنِ أكْذِبَ عَلَى اللهِ ﷻ