Vyshyvanka not only speaks of its Ukrainian origin but also of the particular region in which it was made. The knowing eye could detect where a person hailed from by the clothes on their back. Embroidery is thus an important craft within Ukraine and different techniques exist to suit local styles with their own particular patterns and colours. Traditionally, the thread was coloured according to local formulas using bark, leaves, flowers, berries and so on. In this way, the local environment is literally reflected in the colour of the embroidery.
Read more in Wikipedia or check this amazing Washington Post article.