Tu Bishvat (Hebrew: טו בשבט) is a Jewish holiday, occurring on the 15th day of the Hebrew month of Shevat (in 2013, Tu Bishvat will start from sunset on 25 January and finish at nightfall on 26 January). It is also called "Rosh HaShanah La'Ilanot" (Hebrew: ראש השנה לאילנות), literally "New Year of the Trees." In contemporary Israel the day is celebrated as an ecological awareness day and trees are planted in celebration.
The name Tu Bishvat is derived 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. Tu Bishvat is a relatively recent name; the date was originally called "Ḥamisha Asar BiShvat" (חמשה-עשר בשבט), which also means "Fifteenth of Shevat".