Surah 37. As-Saffat, Ayah 146

I.e., to shade and comfort him. Thus, rounding off the allegory of Jonah and the fish, the Qur'an points out in the figurative manner so characteristic of its style that God, who can cause a plant to grow out of the most arid and barren soil, can equally well cause a heart lost in darkness to come back to light and spiritual life.

 The squash plant provided Jonah with shade and repelled harmful insects.