The speaker takes a word that might sound like a judgment, "unchurched," and happily claims it. Instead of feeling lacking, they feel like a vacant lot, an empty patch of ground where knotweed and loosestrife can move in. Those are plants people often treat as weeds, so the image turns emptiness into something lively and welcome.
The second stanza widens the idea to "we unchurched," a loose group compared to salamanders. They are slippery creatures that live between water and land, and they make their homes in places where, the speaker jokes, people only go for baptism. Wet, wild places become a kind of alternative sacred space.
In the last stanza, the speaker calls to an owl, and she answers. The language is "Greek to me," so the speaker doesn't fully understand, yet the owl flies in and snaps her bill, a bit of a warning. The mood is playful, curious, and lightly defiant. Contact with nature is real, but it isn't tame or neatly understood.