This is my favorite Bulgarian Holiday, which is celebrated on the 1st of March though Martenitzis are worn until you see a stork. Here's some information from wikipedia: (This is just one version of the story) Tradition
On the first of March and the first few days after, Bulgarians give to one another white and red tassels or small wool dolls called "Pizho and Penda", or "Martenitsi". Additionally, in Bulgarian folklore the name Mart is related to a grumpy old lady whose mood shifts very rapidly. Her name is Grandma Marta, in Bulgarian — Baba Marta (Баба Марта).
The tradition has remained almost the same today as it was when it began. Today Bulgarians give one another the red and white colours to please Baba Marta so that she will not make winter last. In doing so, they hope the spring will come as soon as possible. Many people wear more than one martenitsa, which they have received as presents from relatives, close friends and colleagues. Martenitsa is usually worn on the clothes pinned near to the collar or on the hand tied around the wrist. The tradition calls for wearing the martenitsa until the person spots a stork for the first time in the season. This bird is considered a harbinger of spring and is evidence that Baba Marta has been pleased and is about to retire. A martenitsa tied to a tree, a symbol of approaching spring A martenitsa tied to a tree, a symbol of approaching spring
The ritual of finally taking off the martenitsa may be different in the different parts of Bulgaria. Some people would tie their martenitsa on a branch of a fruit tree, thus giving this tree the health and luck, which the person wearing the martenitsa has enjoyed while having it. Others would put the martenitsa under a stone with the idea that the kind of the creature (usually an insect) closest to the token the next day will determine the person's health for the rest of the year. If the creature is a larva or a worm, the coming year will be healthy, and full of success. The same luck is associated with an ant; the difference being that the person will have to work hard to reach success. If the creature near the token is a spider, then the person is in trouble and might lack enough luck, health, or personal success.
The martenitsa is also a stylized symbol of Mother Nature. At that early-spring/late-winter time of the year, Nature seems full of hopes and expectations. The white symbolizes the purity of the melting white snow and the red symbolizes the setting of the sun which becomes more and more intense as spring progresses. These two natural resources are prerequisites for life. They are also associated with the male and female beginnings.
Decorating oneself with one or more martenitsi is a very typical and extremely popular Bulgarian tradition. The martenitsa symbolises new life, conception, fertility, and spring. The time when it is worn is meant to be a joyful holiday commemorating health and long life. The colours of the martenitsa are interpreted as symbols of purity and life, as well as the need for harmony in Nature and in people's lives.
This is only one of the many legends, and perhaps not even the best known one, attempting to offer an explanation (in this case a rather implausible one) of how the tradition of creating and wearing martenitsa arose.
Khan Kubrat's five sons went hunting accompanied by their sister Huba. When they reached the River Danube they saw a silver stag. Mesmerized, the men did not dare shoot at it. The stag crossed over to the opposite bank of the river showing them there was a ford.
A bird flew to them bringing bad tidings. Their father, the founder of Old Great Bulgaria was on his deathbed. In his last hours Kubrat wanted to tell his offspring—Bayan, Kotrag, Asparukh, Kuber and Altsek—not to sever the still tenuous link between the different Bulgarian tribes. His sons vowed to defend Bulgaria.
Soon after their father’s death, the Khazars invaded their lands. The Khazar's Khan Ashina succeeded in conquering the capital Phanagoria. Huba, Kubrat's daughter, was taken prisoner by Ashina. Hoping to give her brothers a chance for freedom, Huba tried to commit suicide but was stopped by the guards.
Her brothers kept their vows in different ways. Bayan stayed with his sister and recognized the supremacy of the Khazars. Kotrag went northwards, to the River Volga, while Asparukh, Kuber and Altsek went south to search for a land without oppressors.
The brothers who left secretly arranged with Huba and Bayan to send word by a golden thread tied to the leg of a bird if they were able to find a free land. One day a falcon sent by Asparukh flew into Huba's room and she and Bayan quickly made plans to escape. Just as they were looking for a place to cross the Danube River, Khazar pursuers spotted them and rushed toward them. Trying to find a ford, Huba let the falcon free. She tied a white thread to its leg and handed it to her brother.
Just as the bird was about to take off, an enemy arrow pierced Bayan and his blood stained the white thread.
While both Bayan and Huba managed to reach the land Asparukh had found (present-day Bulgaria) they were mortally wounded. Asparukh rushed to meet his dying brother and sister but could not do anything to save them. After their death he tore the pieces of white-and-red stained thread and adorned his soldiers with them.