Seasons come and go, and that’s a good thing for the expanding Stevens Point Brewery.

The company is completing a brewery addition in its namesake city that will expand annual production capacity by 25%. And much of that growth is the result of Stevens Point Brewery launching a line of seasonal beers in 2007 and 2008, operating partner Joe Martino said Tuesday.

The seasonal brews appeal to craft beer fans who are known for wanting to sample a variety of beers, Martino said.

“It allows us to introduce something new every few months,” he said.

The expansion, to be completed by May 1, includes 6,600 square feet of new warehouse space, new aging tanks and new fermenting tanks. It will allow Stevens Point Brewery to produce 100,000 barrels of beer annually.

Since 2009, the brewery has invested about $1 million to increase capacity and improve its facilities, Martino said.

Stevens Point Brewery produced 80,000 barrels last year, including beer brewed under contract for other companies. About 50,000 barrels were Point’s own brands – amounting to a 14% increase from 2009 sales.

Point’s 2010 sales increase was tied to the launch of 2012 Black Ale, continued strong sales for the Nude Beach Summer Wheat brand, and expansion into Alabama and Georgia.

Nude Beach is one of the brewery’s seasonal brands, a lineup that includes Einbock, Oktoberfest and St. Benedict’s Winter Ale.

Point’s own brands, the company’s more lucrative line of business, typically account for about 60% of its annual production, with contract brewing accounting for the remaining 40%, Martino said. Before the launch of seasonal brands, that split was closer to 50-50, he said.

The brewery also stopped a long-term decline in sales for Point Special, the brewery’s oldest brand, Martino said.

With its growth, Point has added three new jobs over the past six to 12 months, Martino said. The company, which also produces a line of sodas, has about 30 employees, he said.

The brewery expects its sales growth to continue this year, having recently expanded into Texas and North Carolina, Martino said. Point plans to continue to expand throughout the United States.

“We’re looking at controlled expansion,” Martino said.

Point is the second-largest craft brewer based in Wisconsin, according to the Brewers Association, a Boulder, Colo.-based trade group. The association ranks the company as No. 32 on its 2010 list of the nation’s 50 largest craft brewers.