Joel does not mention what he longs for. On the one hand it speaks for itself what he yearns for (look at the disastrous state of the land, the complaint of even the animals). On the other hand he reverently leaves it to God. He does offer some proposals: a gathering of mourning, repentance, and invocation of the Lord, but he does not want to get in the way of God. No one knows better than God himself what is needed for new joy. May God give what is needed. Humbly Joel limits himself to an upward cry.
19 To you, O LORD, I call. For fire has devoured the pastures of the wilderness, and flame has burned all the trees of the field.