Tu B'Shevat - The New Year for Trees Purpose and Date. The minor Festival of Tu B'Shevat (15th Shevat) is one that is today celebrated mainly in Israel. At this time of the year in Israel, the winter has just passed and the sap is beginning to fill the trees with the promise of spring. In Talmudic times, the day was chosen for computing the annual tithes of fruit; today, it expresses the close ties binding Israel to the soil of the Holy Land. Observance. It is customary to eat fruits that grow in Eretz Yisrael. In Israel, some conduct a Tu B'Shevat Seder consisting of readings, cups of different colored wine, and tasting of fruits, which all alludes to the changing seasons of the year, nature, and the "inner" meanings of different types of fruit. It is also customary for children to plant trees on Tu B'Shvat; in Israel, the Jewish National fund proclaimed this day as Israel's Arbor Day.