ENLARGE

SUMMER IN GERMANY means one thing: beer gardens. And while cooling off with a stein of golden beer is the height of leisure, suds—like all things in Germany—are a very serious science.

They’re even regulated by their own law, the Reinheitsgebot, which states that barley, malt, water and yeast are the only acceptable ingredients.

The country today has a flock of (mostly) excellent beers, but it’s the light, smooth-drinking brews that rule the roost. “There were pockets of variety in places like Bavaria, but really, all we had was pilsners and lagers,” says Sylvia Kopp , author of “Barley Hops” (Gestalten, €40). “For decades, there has been very little innovation in the art of brewing.”

But over the past decade, small German breweries have been pushing for their own place at the tap. Inspired by the craft beer scene in America, they’ve been breaking free from the constraints of the Reinheitsgebot and adding new ingredients that are hardly impure.

At Cologne’s Freigeist Bierkultur, Sebastian Sauer and Peter Esser are bottling long-neglected recipes such as Gose and Lichtenhainer, as well as experimenting with classics, like their unfiltered Kölsch. In Bavaria, the 335-year-old Schönram Brewery produced Germany’s first India Pale Ale.

And across the country, microbreweries like Schoppe Bräu, Hopfenstopfer and BrauKunstKeller have been redefining bier with innovative brews. Even big industry is taking notice; in May, Becks released its own amber lager and pale ale.

The German craft beer scene is still in its fledgling days. Mr. Sauer says he sells more beer in the U.S. and Brazil than in the Fatherland. But with so many new brews cropping up each year, it’s only a matter of time before Germans Prost with a pale ale instead of a pilsner.

FINE STEIN // Five German Craft Beers

Kuehn Kunz Rosen Kuehnes Blondes | 4.9% ABV, €2.50

Brewed with wheat and oats, with hints of coriander and orange, this slightly sweet quaff has a tangy aftertaste that makes for easy summer drinking.

Freigeist Bierkultur Abraxxxas Pear Lichtenhainer | 6% ABV, €3.80

Pear juice gives this beer its sour flavor, and the tartness pairs well with the smokiness a true Lichtenhainer requires.

Schönramer Bayrisch Pale Ale | 5.5% ABV, €2

This pale ale is so light it could almost be a pilsner. But don’t be fooled: A strong ale taste leaves a pleasant peppery finish.

Kehrwieder Prototyp | 5.9% ABV, €2.50

Unfiltered, unpasteurized and cold-hopped, this lager straddles the flavors of a pale ale and a pilsner—without having to conform to either.

BRLO Porter | 7% ABV, €2.30

This Baltic porter’s dark color may help it stand out from the crowd, but it’s the rich caramel flavor—coaxed from three different malts—that makes it so enjoyable.