March's full moon — named for the earthworms that reappear as the soil thaws. The signs of spring behind the name, and how to see it.
Short answer
The Worm Moon is March's full moon, marking the thaw: as the frozen ground softens, earthworms return and birds follow. It is the last full moon of winter, falling around the spring equinox — and other peoples called it the Crow, Sap or Lenten Moon.
When is the Worm Moon?
March's full moon — the date shifts a little each year.See 2026 calendar
Why "Worm"?
The name was used by southern Native American tribes who noticed that, as March's soil thawed, earthworm casts reappeared and drew robins and other birds. Northern tribes instead named it the Crow Moon (for returning crows), the Sap Moon (for the flow of maple sap), or the Crust Moon for the thaw-and-freeze crust on the snow.
What it looks like
Falling near the spring equinox, the March full moon is in transition between the high winter moons and the lower spring ones. It still climbs fairly high and looks bright; in many years the March full moon is the one used to set the date of Easter.
Frequently asked questions
Why is it called the Worm Moon?
Because in March the thawing soil brings earthworms back to the surface, a classic early sign of spring noted by southern Native American tribes.
Is the Worm Moon linked to Easter?
Often, yes. Easter is set as the first Sunday after the first full moon following the spring equinox, which is frequently March's full moon.