In Maryland, there hasn't been a critical mass of German-inspired restaurants since at least 1972, when the Deutsches Haus closed officially. But Blob's Park in Jessup has stayed around, improbably, since 1933, and The Old Stein Inn had been open since 1983 until January, when a fire forced it to close temporarily. Last year, Alewife, which bills itself as a high-end beer hall, opened on the west side. Its owner, Daniel Lanigan, already has two others in Boston.

Demczuk himself is betting on the trend. Later in September, he'll start renovation of the old Haussner's at Eastern Avenue and Clinton Streets, where he'll move production of Raven beer and where he'll build a German-style restaurant and beer garden to be called The Raven Brewery and Pub. He's eyeing an opening date in 2013.

Leinenkugel said he got a visit from Jake Miller, Cordish's business partner, a year ago with a proposition: Cordish's Power Plant Live in Baltimore was expanding and they wanted to incorporate a beer garden to the mix.

"They wanted a connection with an obscure yet known brewery that had a fan base and had an interesting style of beer," Leinenkugel said.

Company vice president Reed Cordish, who had kept an eye the growing popularity of beer halls in New York, saw the concept as "ideal for the city and Power Plant Live."

"To do a true beer garden, you need as much outdoor space as you do indoor space," Cordish said. "It's hard to find much outdoor space in Baltimore city. There's very few restaurants that have significant outdoor patios."

With its all-glass interior, it looks like a pristine greenhouse. The walls can be rolled up depending on the weather, and the roof is also movable. At least 32 brands of beer will be on tap — many Leinenkugel's, but also regional brand names.

Overall, the restaurant will be able to accommodate 125 people indoors and outdoors. In the winter, heating lamps will warm the gravel-covered patio and the fireplace will be turned on.

Food at Leinenkugel's will range $6-$22, and beers will cost anywhere between $5 and $13. There will be premium options as well: the restaurant will have two mobile draft tables that will start at a minimum at $120, said general manager Jesse Ochs.

Leinenkugel was accustomed to tourists and curious gawkers coming to the 144-year-old brewery, which seems ripped from a Hallmark card. It sits on a river in Chippewa Falls, in the scenic north woods of Wisconsin.

Until now, they had never considered taking the name outside of Wisconsin. But the offer from Cordish intrigued him because it came with little risk — they're only licensing the brand name to Power Plant Live.

Already popular in the Midwest, Leinenkugel has tried to aggressively expand its footprint in the Mid-Atlantic in the past five years. It's now at 500 liquor stores and groceries in the region, and its opening the in-name-only Leinenkugel's will provide a new audience of customers.

"They took a lot of pressure off of us," he said. "I would hope it's a win-win. We look at it as a long-term build. What we want to be is one of the top five craft brewers in the Baltimore area."

For Cordish, the stakes are higher. As a brand new construction, it will also be an expensive project — $1.6 million, Cordish said. But the developer, who declined to give specific revenue or sale projections, is bullish on the project.

Baltimore beer experts have mixed feelings about the upcoming beer garden.

Dominic Cantalupo, one of the co-founders of Baltimore Beer Week, said the menu is not as adventurous as the one at Max's Taphouse in Fells Point or Mahaffey's in Canton. But he thinks it'll succeed.

"They have a decent bottle selection, enough to get the beer geeks to go there," he said. But even with competition from the savvier beer bars around, "they'll do well because of the sheer number of people at Power Plant."

Still, Cantalupo and Demczuk said if the trend catches on, it'll be slow.

"Just in our beer week, we had 300-plus events," Cantalupo said. "Philadelphia had over 1,100 events. There's a difference in population."

Tarr is also doubtful beer gardens can sustain their momentum. But she doesn't think they'll be as rare as they were before now.

"Beer gardens are going to be around for a while in a very real way," she said.