La Festa della Donna, or International Women's Day is celebrated on 8th March. It began in 1908 to commemorate the 129 women who died in a fire in a factory in Chicago in that year, and also commemorates two other international events: a strike by women garment workers on 8 March 1857 in New York, which led to the foundation of the first women's union in the US, and a strike by Russian women on the same day in 1917.
It is traditional on this day to give yellow Mimosa flowers to women as a sign of respect and solidarity. Women give Mimosa to each other as well.
Mimosa (acacia dealbata) was introduced to Europe from Australia in 1820. It is probably the first tree to flower - as early as January - and its yellow flowers cheer up the winter landscape. This year it flowered so early I wonder if there will be any around to give on 8 March. Someone has thought of that: as an alternative, you can send virtual mimosa!