SEATTLE - Washingtonians, get ready to shed sweet tears of joy: The Walla Walla sweet onion is one step away from becoming the official state vegetable.

Governor Gregoire is set to sign a bill Friday afternoon that will make the Walla Walla sweet onion the official head veggie.  A bill honoring the coveted bulb was passed by the state Senate Thursday, and the House unanimously passed the measure. 

Prized for its exceptional sweetness, the tasty onion is sought after by chefs and foodies during the small window of mid-June through September. They're best eaten raw or slightly cooked, making them ideal for hamburgers and salads.

The move to honor the prized onion began as a class project for seventh-graders at Eatonville Middle School. The bill previously was a project of a Kirkland Junior High teacher, who retired in 2006.

The campaign hit a snag last year when the state's $3 billion potato industry felt slighted and the bill was changed to designate the Walla Walla sweet onion the state's "edible bulb," while the russet potato was named the "official tuber," according to The Seattle Times.  Washington ranks second after Idaho in potato production nationally.

A European import, the Walla Walla sweet onion came to Washington over 100 years ago when a French soldier found a sweet onion seed on the Island of Corsica, off the west coast of Italy and brought it to the Walla Walla Valley.  Growers have since cultivated it over the years.