... is on December 4 which is today.
The tradition of St. Barbara's day is to cut off some branches from cherry, apple, plum, or other trees. The branches are supposed to bloom until December 24 at the latest, bringing a bit of beauty to the home during the cold and dark time to come. Moreover, the blooming branches are said to bring good luck for the coming year.
I have never tried it before but I just went outside and cut off some branches of our cherry tree. I mean, we all can do with a bit of luck, so I will give it a try! ;-)