"For the LORD God had not caused rain to fall" (Genesis 2:5). [Rain] gives drink and quenches thirst, fattens [the soil] and makes it luxuriant and draws forth [growth]. What is the verse [that proves this]? "You water her furrows abundantly, You settle her ridges, You soften her with showers, You bless her growth" (Psalms 65:11).
The Rain That Waters, Fattens, and Sweetens the Ground
Yalkut Shimoni on Torah 20:2
כִּי לֹא הִמְטִיר מָטָר מַשְׁקֶה וּמַרְוֶה, מְזַבֵּל וּמְעַדֵּן וּמַמְשִׁיךְ, מַאי קְרָאָהּ (תהלים סה, יא) "תְּלָמֶיהָ רַוֵּה נַחֵת גְּדוּדֶהָ וְגוֹ' צִמְחָהּ תְּבָרֵךְ".