.
Ibn Mas`ud (May Allah be pleased with him) reported:
Messenger of Allah (salAllahualahy wasalm) said:
"I met Ibrahim (Alahy salam) on the Night of Ascension (Al-Asra),
and he said to me:
`O Muhammad, convey my Salam to your Ummah,
and tell them that Jannah has a vast plain of pure soil and sweet water. It is a plain levelled land.
The plants grow there by uttering:
سُبْحَانَ اللهِ، وَالْحَمْدُ للهِ،
وَ لاَ إِلَهَ إِلاَّ اللهُ وَاللهُ أَكْبَُر
[At-Tirmidhi]
Commentary:
Qi`an is the plural of Qa` which means plain levelled land that does not have any tree. Trees grow on the plain land of Jannah in return for remembrance and Glorification of Allah. The more one remembers Allah, the greater is the number of trees which grow on the piece of land that will be awarded to him
Riyad-us-Saliheen – Hadith No: 1440