Tu Beshvat, the 15^th day of the Hebrew month of Shvat, is first mentioned in the first mishnah of the Talmudic tractate of Rosh Hashana as the New Year for trees. This has halachic implication with regards to calculation of the three years of orlah, during which all fruits of the tree are forbidden, the fruits of the sabbatical year, and the calculation of tithes. This date was chosen since the trees begin to rise from the winter slumber, as is visible in the flowers of the Almond tree (one of the first to blossom).

According to Kabbalistic concepts, this day has significance as the time of year when the winter is beginning to pass. Light is good and redemption, while darkness is regarded as bad and misfortune. In the winter the light of the days is short and the darkness of the nights long; this begins to take turn at Tu B’shvat which is regarded as the first sign of regeneration within the misfortune.

The Kabbalistic sages made a sort of "Seder night" on Tu B’shvat, drinking four cups of wine. The first was white wine symbolizing the lifeless slumber of the winter. The second was a mixture of both red and white while the majority is white symbolizing the arising of the creation from the slumber of the winter. The third had more red than white, and the fourth was completely red. The white wine symbolizes the pale light of the moon which is visible during the long nights of the winter, while the red wine is the strong light of the sun.

The popular custom today is to eat from all the seven types of fruit with which the land of Israel is praised and blessed (wheat, barley, grapes, figs, pomegranates, olives, and dates - Deuteronomy 8:8-9).