Katherine and Delano DuGarm, both government employees in their 50s, have seen hundreds of Minnesota Fringe Festival performances over the past decade or so.

The couple, married 21 years, recall both stunners and stinkers at the unjuried performing-arts free-for-all. “The William Williams Effect,” Brian Columbus’ 2009 drama about the last person executed in Minnesota, was indelible, they agree.

Alhough they’ve never walked out of a show, they wanted to at one “that was entirely a PowerPoint presentation,” said Delano. “I know how to do a PowerPoint presentation, and that wasn’t a good one. But I’m not going to say who made the choice to go to that show.”

“Smart man,” said Katherine.

The DuGarms, who see 20 to 30 shows a year, are diehards of the Fringe Festival, which is celebrating its 20th season. They spoke Monday on the deck of the Minnesota Centennial Showboat, where they attended a preview showcase at which 30 acts presented snippets of their Fringe shows. (There is a showcase of out-of-town Fringe acts on Wednesday, the eve of the festival’s opening.)

At the sampler on the boat, audiences responded enthusiastically to “The Nose,” a “Sweeney Todd”-style show about a barber who accidentally cuts off a client’s proboscis; “Are You There, God?” a charming musical revue by Blue Umbrella; “Four Humors’ Lolita: A Three Man Show,” in which Lolita is played by a hairy guy in a polka-dot bikini; “Standing on the Hollow,” a dance piece starring Tamara Ober accompanied by flutist Julie Johnson, and the poignant transgender tale “Changing With Grace: When Daddy Becomes Mama Christy.”

How big is the Fringe?

Since its founding in 1994 by Bob McFadden, the Minnesota Fringe Festival has grown exponentially and has hooked many who make an annual pilgrimage to its one-hour comedies, musicals, dramas, storytelling, dance and puppet shows.

It started with 53 productions in six venues; it now has 176 at 16 performance sites, including new venues on Hennepin Avenue in downtown Minneapolis (the New Century and James Sewell Ballet TekBox). In its first year, the Fringe drew 4,600 patrons. Last year, attendance was more than 46,000. And the budget also has risen, from $35,000 in 1994 to about $700,000 last year, according to Fringe officials.

“The question that the Fringe has to face is, ‘What is the right size for the festival?’ ” said Robin Gillette, executive director, who is leaving this year after what will be her seventh festival. “If we extend it to St. Paul and Bloomington, are we going to lose some of the essence of the Fringe? The fact that people can park on the West Bank and commit a day there, or do the same in Uptown — that quality is an indispensable part of the Fringe experience.”

That quality attracts Jason Greene. He may live in South Carolina, but Greene has flown in for each of the past eight years for the 11-day festival.

“I have a great time,” said Greene, 40, who stays with relatives in Burnsville and Fringe-hops, seeing as many as 20 shows.

“It’s like we’re a tribe of people, you know,” he said. “You get to meet new people. You get to try new things.”

Greene gravitates toward anything by the Scrimshaw family and the comic duo of Mike Fotis and Joe Bozic, who are affiliated with the Brave New Workshop. The Scrimshaws are involved in four shows this year: “Comedy vs. Calories: FIGHT!” “How to Swear Like a Minnesotan,” “To Mars With Tesla or the Interplanetary Machinations of Evil Thomas Edison” and the dance show “Heatwave.” Fotis and Bozic this year are doing “Hickory Minimum Security Correctional Facility Presents: Hoosiers: The Stage Adaptation,” a new, adult-appropriate show about competitive prison theater.

So much to see

The Fringe bingers are a special breed. They see lots of shows, buying 10-show cards or Ultra Passes ($225), which allow viewers to see up to 56 shows — one for each slot programmed. Some Fringe fanatics see shows through a combination of paid tickets and volunteering; the festival has more than 400 volunteers.

Will and Brenda Weisert both volunteer and see shows. This will be the 50-something couple’s fourth Fringe together — they got married in 2010. They expect to match last year’s total of more than 50 shows seen, and to continue seeking out comedies and storytellers.

“Ninety to 95 percent of the shows that we’ve seen have been worth the hour that we gave to it,” Will said.

He remembered the worst thing he saw, an interactive show at the Rarig proscenium stage on the West Bank.

“It was supposed to be an interactive, funky melodrama,” he said. “There were 12 people in the audience. Then they called for volunteers. We were all dying.”

“That’s the beauty of the Fringe,” said Gillette, who will be replaced by associate director Jeff D. Larson, who began his career at the festival in 1999 as a venue technician. “You get the whole range of experiences, and you get it for a bargain.

“Where the festival goes the next 20 years is anyone’s guess.”