The Jewish calendar marks four new years:
a governmental new year starting on the first day of the first month; a religious new year starting on the first day of the seventh month– Rosh HaShanah;
a new year for tithing livestock (as donations to the Temple) on the first of the month of Elul; and a new year for trees on the 15th (Tu) day of the month of Shvat.
Why a new year for trees and not vegetables? Why on the 15th and not on the first of the month like the other three new years?
First, why a new year for trees and not vegetables? Vegetables have only one cycle of growth and decay in a year. Vegetables fulfill their whole life within one year.
Trees live on for many decades, offering their fruits and nuts to many generations of birds, insects and other living things.
And there are some species of trees that live for centuries, recycling the air we all need to breath, and reminding humans of the importance of long term thinking and being.
Tu Bishvat highlights the perennial rejuvenation and blooming of trees (nature); and also the constent reform and renewal of the Jewish people and its religious life (culture).
Human-beings are likened to trees of the field (Deuteronomy 20:19) and a tree is a good metaphor for family (a family tree) Just like the tenacious trees on hillsides and flood plains, human beings need to be deeply rooted to survive rough times.
Like trees, human-beings are capable of withstanding many adversities if they have deep roots (religious values and traditions) and a solid, healthy trunk (a close community). At the same time they need to have flexible leaves and branches (to change and reform).
The state of the roots impacts directly on the state of the trunk, leaves and branches. The state of the roots determines both the future of trees and human beings.
Healthy roots facilitate the blossoming of next years fruits and sprouts.
In the Hebrew word for tree – Ilan (אילן) – are the two first letters, אל, God. The Hebrew spelling for the rugged, Biblical terebinth and oak tree is אלה and אלון, both starting with the two letters, אל, God.
Jewish mystics would add that the mathematical value of Ilan is 91, which is the sum of Khavayah-being/existence /YHVH, and Adonai-Lord. So the phrase Lord God=Tree (of Life).
The Tree of Life is first mentioned in Genesis (2:9), next to the Tree of Knowledge of good and evil. The Tree of Moral Knowledge enables humans to discern, distinguish, and decide between right and wrong (free will and reason).
The Tree of Life adds an emotional, spiritual, experiential aspect, as a greater context to our moral life.
A tree is not just an object whose products (lumber, fuel, fruits and nuts) are useful.
A tree is also a subject whose beauty is an integral spiritual part of nature, reflecting vitality and growth, nurturing and sheltering in its environment.
Thus, a mighty oak tree is a good symbol for the long lasting presence of spiritual forces both within the natural and the spiritual world.
According to Genesis 1:11, trees were created on the third day/stage of Creation, the only day/stage which was blessed twice by God.
So humans have a special responsibility to protect trees as a double blessing; for ourselves and for our descendants. That is why the Torah (Deuteronomy 20:19/20 ) commands us:
“When you besiege a city… you shall not destroy its trees by swinging an axe against them; you may eat from them, but you shall not cut them down… Only the trees which you know are not fruit trees may you destroy and cut down….”
Even in war times Jews may not choose to use short term advantage at the expense of long term benefits. If that is true for war how much the more so just for short term economic benefits.
Jews must also plant trees, thus planning ahead, for future generations. As the Torah (Leviticus 19:23) stipulates:
“When you come to the Land, you shall plant fruit trees.” i.e. don’t just live off the efforts of others, build for the next generation.
Now to the second question: Why on the 15th and not on the first day of the month of Shvat; like the other three new years mentioned in the Mishnah – the collection of Jewish oral laws, compiled by Rabbi Yehudah Hanasi around 200 CE.
Actually, the Mishnah records a dispute of two leading first century BCE rabbis between the 15th and the first day of Shvat.
Shammai and his disciples maintained that it was only logical that a new year should always start on the first day of the month. That is the way it had always been done.
Hillel and his disciples felt that trees were different. The Biblical Book of Proverbs says: “She (Torah wisdom) is a tree of life to those who take hold of her, and those who support her are fortunate” (3:18).
Since Torah wisdom sees trees as both spiritual and practical. the new year for trees should begin on the full moon, like the Jewish holy days of Passover and Sukkot. when the greatest things happen (the redemption from slavery in Egypt; and the harvest of natures’ fruitfulness).
The ability to see the world with two eyes; one practical and the other romantic, is vital to a healthy religious life. Jews do not worship nature as did many of our neighbors in Biblical days.
Neither should we simply use nature for our own purposes alone. The Torah tells us that: “The Lord God put mankind (Adam means the species in Hebrew) into the Garden of Eden (nature): ”to take care of it and to look after it.” (Genesis 2:15)
A Tu Bishvat Seder; a ritual celebrated by eating 15 kinds of nuts and fruits and drinking four different kinds of wine (some rabbis considered the grapevine a short tree because it can live for many decades) can be conducted on Tu Bishvat eve, recounting the importance of trees and fruits from the land of Israel and the personal spiritual significance of Tu Bishvat.