The poem is a tiny scene built on a pun and a surprise. "Mother" has a second meaning here: the mother of vinegar, the cloudy, living film that forms on wine as it turns sour. So when we read that "the mother" is talking to the wine, we can picture a family at the end of a meal, but also a strange kind of conversation between the substance that sours wine and the wine itself.
The phrase "how to stay lit" is the heart of it. Wine glows, and so do people at a dinner table, warmed by drink and talk. Staying lit means holding on to that glow, and the poem hints that it can't last. The wine will turn, and the evening will end.
The mood is quiet, wry, and a little wistful. The speaker doesn't comment or complain, just lets the image sit there. There is humor in the wordplay, but also a gentle sense of time passing and good things souring.