I planted some of my corn starters this week among the kale that I planted last fall.
This is the process of progressive planting in a garden. Planting new starters near the end of the last crop so you get overlap of production. And since many of the corn starters are very small still (holding one in my hand in the photo below), they are not a problem now for the kale.
The kale is almost done, and by the time the corn grows large enough, the kale will be already removed. But the kale still has some production left it in. So no reason to waste the space when there is time to do both in that space in the same time.