JERUSALEM -- At an open-air fruit stand in Jerusalem's ultra-Orthodox Mea Shearim neighborhood, seminary student Samuel Bloch poked at a lemon-like citron, inspecting it with an exacting eye.

"It needs to be clean, smooth and there can be no black spots at the edge. It can't be too heavy, and it especially can't be bruised," said the 21-year-old Paris native. The fruit vendor urged him to wait, a new delivery had just arrived.

Across Israel, shoppers wrapped up such painstaking tasks in preparation for Sukkot -- the Jewish harvest festival that began at sundown Friday and lasts for a week.

The celebration, as with most Jewish holidays over the past two years of conflict with the Palestinians, was overshadowed by concerns of violence -- a recent surge of suicide bombings and warnings by Islamic militant groups of more to come.

A central feature of the holiday involves reciting blessings over four species of plants native to the Holy Land -- palm, myrtle, willow branches and a rare citrus fruit known as citron. Each day they are carried in processions in synagogue.

Many Jews moved into temporary housing for the festival, the observance of which includes building a hut outside the permanent house and eating meals there all week. Some Orthodox Jews move their families into the temporary structures and live there throughout the festival. The huts are covered with tree branches, and many are brightly decorated with streamers and pictures.