This question likely comes from the differences in phrasing of the second question of "Ma Nishtana", the set of four Passover questions. The question is, "On all other nights we eat many vegetables, why on this night, [only] bitter herbs?". The word "only", put in brackets here, is inserted in some versions and removed in others. This is likely a problem deriving from remembering the questions of "Ma Nishtana" incorrectly, because the first question has a similar format: "On all other nights we eat both leavened and unleavened bread, why on this night, only unleaveaned bread?" Since the format was similar, the "only" in the first question, which is legitimate - no leavened products are eaten on Passover, it was incorrectly carried to the second question.
As others have noted, Jews eat a variety of other vegetables on Passover, most notably the "karpas", which is a piece of parsley or celery that features in the Seder celebration. Additionally, most Jews will include some vegetables in the meal that is served during the meal-portion of the Seder. So, the premise behind the question of "only" is incorrect.
The Passover (Pesach) Seder is a special festive meal held on the night of Passover. In it, Jews tell of the Exodus (From a book called the Haggadah) and have specified foods (including matzoh and bitter herb).
The seder plate typically holds 5 or 6 items symbolic of the Passover meal: The shankbone of a lamb, a reminder of the Passover sacrifice (a chicken bone or a beet can be substituted). Bitter herbs, for the commandment that you shall eat it with matzah and bitter herbs. Charoset, a relish made of fruit, nuts and wine, symbolic of the mortar used by the Israelite slaves. A green vegetable, usually parsley, symbolic of spring and intended to dip in salt-water symbolic of the slaves' tears. A roasted egg, a symbol of the festival burnt offering (as distinct from the Passover sacrifice). (optional) a second bitter herb because there are two points in the Seder when bitter herbs are consumed.
It is set on the table during the Passover seder (the first and second nights of passover).
The seder plate represents key elements of the Passover story and traditions. The various items on the plate symbolize different aspects of the Exodus from Egypt, such as the bitter herbs representing the bitterness of slavery and the matzah representing the haste of the Israelites leaving Egypt. It serves as a visual and symbolic centerpiece for the Passover seder meal.
The Seder plate is a special plate used during the Passover Seder meal in Jewish tradition. It holds symbolic foods that represent various elements of the Exodus story and the Jewish people's journey to freedom. Common items on the Seder plate include bitter herbs, a roasted shank bone, a mixture of fruits and nuts, and a boiled egg.
during a passover seder.
The holiday of Passover officially begins on the evening of Monday, March 25th (in 2013). Most people who celebrate Passover will have a seder either on the 25th or the 26th.
night of passover
The seder plate. See also:More about the Seder
The ritual foods at a Passover seder are Matzah (unleavened bread), Maror (bitter herbs), Karpas (a green vegetable, usually parsley), Beitzah (a roasted, hard boiled egg), Haroset (a mixture of apples, nuts, cinnamon, wine) and Z'roa (a shank bone, usually represented by a turkey neck or a beet). Four cups of wine are traditional as well. The main course can be almost anything, as long as it complies with Passover dietary laws.
Horseradish is eaten during the Passover Seder in order to recall the bitterness of the slavery. Eating bitter herbs is mentioned in exodus ch.12.
Maror is the bitter herbs which we eat in the Passover Seder meal (Exodus ch.12) to commemorate the bitterness (Exodus ch.1) of the Egyptian slavery.