All Living Things From Water
From reading this tafseer here https://www.javedahmedghamidi.org/#!/quran?chapter=21¶graph=1&type=Ghamidi#fn_213 It seems to me that its an expression of saying that water is needed for plantation. In an explanation, it has been written that the life is dependent on water. http://www.al-mawrid.org/index.php/questions/view/creation-in-pairs-and-everything-created-from-water-is-the-quran-scientific