Ibn Umar (Allah be pleased with them) reported Allah's Messenger' ﷺ as saying: Do not buy fruits (on the trees) until their good condition becomes clear. In the hadith transmitted on the authority of Shu'ba it was stated that Ibn Umar (Allah be pleased with them) was asked what good condition implied. He said: When (the danger of) blight is no more.

حَدَّثَنَا يَحْيَى بْنُ يَحْيَى، وَيَحْيَى بْنُ أَيُّوبَ، وَقُتَيْبَةُ، وَابْنُ، حُجْرٍ قَالَ يَحْيَى بْنُ يَحْيَى أَخْبَرَنَا وَقَالَ الآخَرُونَ، حَدَّثَنَا إِسْمَاعِيلُ، - وَهُوَ ابْنُ جَعْفَرٍ - عَنْ عَبْدِ اللَّهِ بْنِ دِينَارٍ، أَنَّهُ سَمِعَ ابْنَ عُمَرَ، قَالَ قَالَ رَسُولُ اللَّهِ ﷺ " لاَ تَبِيعُوا الثَّمَرَ حَتَّى يَبْدُوَ صَلاَحُهُ " .