The 500-foot vine will be in bloom for Sunday’s Sierra Madre “Wisteria Fete.”

Ninety-eight years ago, a wisteria seedling from a one-gallon, nursery can was planted next to a house in the foothills of Sierra Madre.

By 1913, the vine had grown so big that it engulfed the house. An arbor was extended over the roof. But finally, the roof collapsed under the weight of the magnificent plant with its light, fragrant, ever-creeping lavender blossoms.

By 1918, the city of Sierra Madre held its first public festival to celebrate the vine, which eventually was listed in the Guinness Book of World Records as the world’s largest blossoming plant.

The thick branches now cover one acre, stretching as far as 500 feet, and weigh an estimated 250 tons.

Once a year, the wisteria vine, located on parts of two residential properties, goes on public display. And Sunday will be day for this year’s viewing.

Sierra Madre’s boosters say the plant has been

declared one of the “Seven Horticultural Wonders of the World”--in the same company as the gardens at India’s Taj Mahal and England’s Buckingham Palace.

“It’s in full bloom now and will be for several weeks more,” said Fran Syverson, one of the scores of volunteers working on the tiny city’s “Wisteria Fete.”

The festival will be from 11 a.m. until 4 p.m. Every 20 minutes, starting at 10:40 a.m., shuttle buses--based just north of the intersection of Baldwin Avenue and Sierra Madre Boulevard--will ferry sightseers to the vine in the foothills. Round-trip tickets cost $1 per person.

The event also will include a street and food fair, from 9 a.m. to 5 p.m., in Sierra Madre’s business district.

Information: (818) 306-1150.