Six short lines, no punctuation, no capital letters except the solitary "I", and yet the poem ends by prying a single word apart. That is the real event here. Everything before the last two lines is preparation: a season, a wish, a job done in the dark.
The opening is bare. "winter and all I wish is silver / a true sail". The phrase "and all" can be read two ways: winter and everything that comes with it, or "all I wish" as a narrowing, so that the season has stripped desire down to one thing. Silver suggests the colour of winter light, frost, or moonlight on water, though it might also hint at money, and the poem never decides. The second line has no verb. "A true sail" simply hangs there like an image on a horizon. "True" does a lot of work: a sail set true holds its course, and a true thing is also an honest one. The speaker doesn't ask for warmth or company, only for something that moves cleanly and steadily through a season when nothing else does.
Then comes the longest line, left alone in its own stanza: "I am writing a history of midnight". Midnight is a hinge between two days, not a stretch of time, so a history of it should be almost empty. The line seems to say that this is the point, and that the speaker is recording what usually goes unrecorded. The present continuous matters too. "I am writing" suggests a job still in progress, as if the night shift never really finishes. The next line borrows the same grammar but grows more honest about effort: "I am making myself see". Seeing is not automatic here. It has to be forced, as the eyes must be in the dark. The verb has no object, so we are left asking what the speaker is trying to see, and the poem lets the midnight, the winter and the silver all stand as possible answers until the last stanza answers for them.
"so great a difference / between take and care". Starting in lower case, the line sounds like a thought arriving mid-breath, and the title now makes sense. "Caretaker" is a word we use without noticing its seams. It usually means someone who looks after a place when others have gone home, which suits a winter midnight well. But the poem splits the word into its two halves and finds them opposed: to take is to grab and possess, while to care is to tend and pay attention. Sound sharpens the effect. In "take and care" the hard k of one word runs straight into the k that begins the other, so the two sit almost touching in the mouth while their meanings pull apart. The poem also ends on "care", not "take", so the last word is the one it chooses.
Judging by the imagery, the poem may also be quietly correcting its own opening. A wish for silver sounds like wanting to have something, a little like taking. The rest of the poem is about a different kind of activity, keeping watch and writing down what no one else is awake to see. That reads as care, and the speaker seems surprised to find how far apart the two are. The poem doesn't state any of this, so the reader has to make the connection.
The form supports the idea. The stanzas run two lines, one, one, two, a symmetrical frame with the two single lines in the middle like a pair of lit windows. The white space between them works as the dark. There is no rhyme and the rhythm is loose, so the little ripples of sound ("silver", "sail"; "midnight", "making", "myself") carry the music instead.
The poem is significant for how much it does with so little. It takes a word we say automatically, and a phrase like "take care" that we say on parting, and asks us to hear the choice inside them. Reading it, you may find yourself testing the difference in your own life: what do you take, and what do you care for, and which of those do you do when no one is watching?