Green is a holy color in Islam
Er, no, Islam doesn't have any
holy colors. What is true, however, is that green is a praised color in Islam by association with Paradise (e.g. the righteous will be clothed in green garments), the figure of "Al-Khidr" (lit. "the Green One"), and that one hadith had the Prophet Muhammad (peace be upon him) name "greenery" is one of three universally good things (the other two being "water" and "a beautiful face"). Also, some of the Caliphates used green as the color of their standards, while the Ottoman Empire tended to reserve green as the color of religious institutions.