On every day of the holiday of Sukkot (with the exception of Shabbat), there’s a mitzvah to take the “Four Kinds”—a lulav (date palm frond), an etrog (citron), at least three hadassim (myrtle branches) and two aravot (willow branches). In the words of the verse (Leviticus 23:40), “You shall take for yourselves on the first day the fruit of the hadar tree [citron], date palm fronds, a branch of a braided tree, and willows of the brook, and you shall rejoice before the L-rd your G-d for a seven day period.”