LEWISTON — Demand for Baxter beer has been so great that the fledgling Bates Mill-based brewery announced plans to double its current production Monday, less than three months after its first cans hit store shelves.

“Demand has been absolutely phenomenal,” Baxter founder Luke Livingston said in a news release Monday afternoon. “We’re just now coming into peak beer season in Maine, but demand has already exceeded our capacity.”

In order to boost production, the company will purchase two new fermenting tanks as well as a new conditioning tank. The tanks are expected to arrive in early June.

The new equipment will allow the company to brew twice as much beer and increase monthly production from about 300 barrels, or 4,200 cases a month, to closer to 600 barrels a month. With more beer flowing, the company will hire additional workers, and the new tanks will also give Baxter room to experiment with a third variety to add to its lineup, which currently includes just two styles, the Pamola Xtra Pale Ale, a lighter beer, and the Stowaway IPA, a hops-heavy, full flavored brew, Livingston said.

While no decisions have been made about what the new style will be, the company will begin experimenting with new recipes and have test batches available for tasting at the Baxter retail shop in the Bates Mill complex in a few weeks, Livingston said in a phone interview Monday evening.

Meetings with the brewery’s distributor made it clear that the company had to expand quickly, he said. “It’s happened sooner than expected,” he said. “The fact that we’re growing so fast is something that no one could have anticipated, but it shows that we are really filling a high-demand niche.”

“It’s a little overwhelming, but we’re still excited.”

The Baxter beers have disappeared from store shelves so quickly that the company has been challenged trying to fill orders, Livingston reported. Their distributor, Pine State Trading Company of Augusta told them that “100 percent of (stores) who ordered shipments from the first batch of beer, in January, reordered in February, and 80 percent of them increased the size of their orders,” he said.

The company’s experiment with slow-brewed, handcrafted beer — their three-week brewing, fermenting, and conditioning process is longer than the typical Maine microbrewery’s — and willingness to buck the glass-bottle trend that dominates New England’s microbreweries, seems to be paying off, Livingston said.

“We have some great, unique beers. And we’ve shown that cans really are superior packaging,” Livingston said. “We knew the market was ready for us, but we’ve been surprised and thrilled by how enthusiastic everyone has been.”

“Of course, this also means that we have to reopen the walls of Bates Mill sooner than we had planned, in order to move in the new tanks. If we knew we were going to grow so quickly, we might have installed a garage door instead.”