Oxalis-per-caprae or Bermuda buttercup is not a native Cretan flower but originates from South Africa. It is a highly invasive flower and is fast taking over large tracts of cultivated land.
Right now, in February, where few native plants are flowering it is definitely the most prevalent flower in many areas (and along many roadsides) so it earns its place as flower of the month.
Many bee keepers like Oxalis because it provides much needed pollen for their bees at a time when flowers are still scarce. On the other hand botanists tend to hate it because it threatens native flowers as it takes over more and more areas.