Grandma March Day (or simply Baba Marta, Bulgarian: Баба Марта) is a holiday celebrated in Bulgaria, on the first of March.

Martenitsas - usually in the form of a wrist band or small yarn dolls or tassels, created by combining red and white colored threads - are worn on that day and through March, until a stork or a blossoming tree is seen, symbolizing the coming of spring, warmer weather and well being. Once the stork or blooming tree appears, the Martenitsa is taken off and hung on a tree. It is common in the spring to see trees festooned in Martenitsas.

The greeting exchanged on this day is Chestita Baba Marta (Честита Баба Марта – Happy Baba Marta, often shortened to ЧБМ on greetings cards).