Nowruz falls at the exact moment of the spring equinox and marks the first day of the Iranian solar calendar, a festival with roots that predate Islam in Iran and that the Zoroastrian tradition, Iran's dominant religion before the seventh century Arab conquest, kept as its own great feast of renewal. Sabzi polo, rice cooked with a generous mixture of fresh dill, parsley, coriander, chives and sometimes fenugreek folded through the grains until the whole dish turns green, is one of the festival's most consistently served foods, usually paired with fried or grilled fish, particularly around the New Year itself.
The herbs are read directly as a sign of the spring the festival celebrates, green growth breaking through after winter, echoing the wheat, barley or lentil sprouts, sabzeh, grown specifically for the Nowruz table and displayed as one of the seven traditional items, the haft sin, set out for the holiday. Zoroastrian households historically treated Nowruz as a religious feast tied to Ahura Mazda and to the renewal of creation itself, and fire, another central Zoroastrian symbol, is honored in the Nowruz season through Chaharshanbe Suri, a festival of jumping over bonfires held on the last Tuesday eve before the new year.