Quinoa, a grain-like crop grown in South America, is not one of the grains considered chametz (wheat, barley, rye, oats, spelt, or their derivatives). Some medieval Ashkenazi rabbis ruled that kitniyot (legumes) could not be eaten during Passover because they could be confused with chametz products. Some authorities consider quinoa to be kitniyot, while others do not.
Tu BiShvat (Hebrew for the 15th day of the Hebrew month of Shvat) is the new year of the trees.
Tu BiShvat, called the "New Year of the Trees," falls at a seemingly incongruous time of year.
Tu BiShvat is a minor festival whose provenance dates only to the time of the Second Temple. However, the kabbalists who clustered around the great fifteenth-century mystic Isaac Luria of Safed placed great weight on the holiday, creating new festivities, gatherings at which hymns were sung, fruit (particularly carob) was eaten, and four cups of wine were taken (as in the Passover seder).
Sukkot, the Jewish festival of booths (a harvest holiday of thanksgiving), begins on the 15th day of the Hebrew month of Tishrei.
According to Jewish custom, it is preferable to visit graves before a holiday, so that on the day of the holiday, we can focus attention on observing or celebrating.