The T’u Beshvat seder moves through the Kabbalistic four-world model: 

Assiyah: Earth / Action / Physical / Winter

Yetzirah: Water / Formation / Emotion / Spring

Atzilut: Fire / Emantation / Spirit / Summer

Briyah: Air / Creation / Thought / Fall 

Each world has its own type of fruits, and wine  associated with it. When you attend a seder, you are welcome, but not required, to bring them. 

Here are some examples:

Assiyah: fruits with an inedible outer shell/peel (ex: banana, almond, pomegranate, orange) + white wine

Yetzirah: fruits with an inedible pit/seeds (ex: peach, plum, apple, date, cherry, olive) + white wine with a little bit of red (about ⅓ red, ⅔ white)

Briyah: completely edible fruits (ex: berries, figs) + red wine and white wine mixed more evenly (about ½ each)

Atzilut: no fruit, but you’re welcome to bring herbs or spices to smell + red wine (all-red)

You are welcome to substitute grape juice for wine in all cases!

Hadar goes on to instruct: “You’re invited to spend some time among trees in preparation for Tu Bishvat—even for just a minute!—and you may participate in and engage with this seder however you want. Some suggestions to help make your space and this experience special: Bring art supplies, light a candle, sit near house plants, gather objects that represent aspects of the four worlds. Or you can just show up and be present, no preparation needed!”