By the piano of my ancestral establishment lives a two-volume collection of German folk songs, and in that collection is a special section for Mailieder. I am wildly in favor of having an entire genre of songs devoted to May, and its traditionally associated joys of sunshine, going for long walks, and falling in love. Here is my favorite of these songs, "Der Mai ist gekommen."
Erich Kunz, with photographs which, I swear, could have been taken on some of my 1st May Wandertage of years past:
And as a bonus, here is Fritz Wunderlich singing--what else?--"Im Wunderschönen Monat Mai," from Dichterliebe: