Rich Carriero examines a few holidays, green and otherwise, that fall in April each year.

1.   Tulip Festival – Contrary to common belief, the tulip came to the Dutch from the Ottomans and not the other way around.  Tulips are indigenous to Iran and Persian culture had an enormous amount of influence over the Ottomans; thus the flower was imported.  During the 17th Century the Ottomans began to overhaul their public image, showing a heightened interest in art, architecture and gardening.  One particular Grand Vizier during the period had a strong love of tulips and set the fashion.  Within a few years people were spending gobs of money on pretty flowers.  Tulips came to be incorporated in intricate designs on porcelain tile work and flatware.  The ‘Tulip Period’ is now widely regarded as a late Ottoman Golden Age during which the arts flourished and Turkey began to orient itself towards Europe.  Today in Istanbul the municipal government plants thousands of tulip bulbs throughout the city.  The flowers bloom in late April and dazzle the city with colour for weeks.
2.  Earth Day – Earth Day, which falls on April 22nd of each year, began in 1970 as part of a groundswell of environmental initiatives that ultimately culminated in the Clean Air, Clean Water and Endangered Species Acts.  The first Earth Day was marked by demonstrations throughout the US promoting environmental awareness, which at that time was beginning to take its place among the Free Speech, Civil Rights and Anti-War movements.  Over the years the holiday has transcended national borders as concern over Global Warming has mounted.  The spirit behind earth day is not merely one of awareness toward the perils of our world, however, but also a celebration of the planet that nurtures us all.   
3.  4/20 – April 20th enjoys the dubious honour of hosting another holiday of the “green” variety.  4/20 is basically International Smoking Weed Day.  Although the whole day is devoted to appreciation of Cannabis sativa, the high points are at 4:20 AM and PM when legions of stoners all over particular time zones light up in unison.  Like any drug icon, the origins of 420’s significance are apocryphal.  According to the infinite wisdom of Wikipedia one founding myth stems from San Rafael high school in California where potheads would convene after detention to smoke up at 4:20 each afternoon in front a statue of Louis Pasteur.  Other common explanations cite 420 as a police code, weight measurement or Grateful Dead lyric.
4.  Tax Day – Although its common to equate tax day with paying money, most people don’t wind up paying anything on tax day because their income tax is withheld by their employers throughout the year.  In fact, many Americans look forward to tax day because at that time they receive large refunds from the government, which citizens are then encouraged to spend patriotically on non-essential luxury items.  The significance of tax day, then, is merely as the day that people compare their own statement of earnings to the records of their state and federal governments and accordingly reconcile any discrepancies.