| Tu BiShvat (Hebrew: ט״ו בִּשְׁבָט, Romanized: Ṭū bīŠvāṭ, lit. '15th of Shevat') is a Jewish holiday occurring on the 15th day of the Hebrew month of Shevat. It is also called Rosh HaShanah La'Ilanot (ראש השנה לאילנות), literally "New Year to the Trees". In contemporary Israel, the day is celebrated as an ecological awareness day, and trees are planted in celebration.
Etymology
The name Tu BiShvat is originally from the Hebrew date of the holiday, which occurs on the fifteenth day of Shevat. "Tu" stands for the Hebrew letters Tet and Vav, which together have the numerical value of 9 and 6, adding up to 15.[a] The date may also be called "Ḥamisha Asar BiShvat" (חמשה-עשר בשבט, 'Fifteenth of Shevat').[2]
Talmud
Tu BiShvat appears in the Mishnah in Tractate Rosh Hashanah as one of the four new years in the Jewish calendar. The discussion of when the New Year occurs was a source of debate among the rabbis, who argued:
The first of Nisan is the "new year for kings and festivals".
The first of Elul is the "new year for the tithe of cattle"; the tannaim Eleazar ben Shammua and Shimon bar Yochai, however, place this on the first of Tishrei.
The first of Tishrei is the "new year for years" (calculation of the calendar), "for release years" (sabbatical-Shmita years), jubilees, planting, and for the tithe of vegetables.
The first of Shevat is the "new year for trees" according to the school of Shammai; the school of Hillel, however, place this on the fifteenth of Shevat.
The rabbis ruled in favor of Hillel on this issue and the 15th of Shevat became the date for calculating the beginning of the agricultural cycle for the purpose of biblical tithes.
Biblical tithes
Orlah refers to a biblical prohibition (Leviticus 19:23) on eating the fruit of trees produced during the first three years after they are planted.
Neta Reva'i refers to the biblical commandment (Leviticus 19:24) to bring fourth-year fruit crops to Jerusalem as a tithe.
The second tithe was a tithe which was collected in Jerusalem and the poor tithe was a tithe given to the poor (Deuteronomy 14:22–29), which were also calculated by whether the fruit ripened before or after Tu BiShvat.
Of the talmudic requirements for fruit trees which used Tu BiShvat as the cut-off date in the Hebrew calendar for calculating the age of a fruit-bearing tree, the orlah remains to this day in essentially the same form it had in Talmudic times. In the Orthodox Jewish world, these practices are still observed today as part of Halakha, Jewish law. Fruit that ripened on a three-year-old tree before Tu BiShvat is considered orlah and is forbidden to eat, while fruit ripening on or after Tu BiShvat of the tree's third year is permitted. In the 1st, 2nd, 4th and 5th years of the Shmita cycle, the second tithe is observed today by a ceremony redeeming tithing obligations with a coin; in the 3rd and 6th years, the poor tithe is substituted, and no coin is needed for redeeming it. Tu BiShvat is the cut-off date for determining to which year the tithes belong.[citation needed]
Tu BiShvat falls on the 15th day of the Hebrew month of Shevat and begins a three-month series (in years without a leap year) of holidays that occur on the mid-month full moons that culminate in Passover.
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