With the arrival of Memorial Day, the time for outdoor parties is here. And whether you’re on the beach, a boat or just in your backyard, I’ve got the key to creating a refreshing and dead-simple bar for any summer party: club soda.

Yes, humble bubbly water is really the only mixer you need for hot-weather parties. It turns a wide range of spirits into light and refreshing two-ingredient highballs. So for your celebrations this season, I recommend setting up a bar with plenty of ice, plenty of club soda and a bottle from as many of the categories below as you feel like. (If you want to get really fancy, add some lemon and lime wedges or fresh herbs for garnish, but they’re just icing on the cake.)


MODERATELY PRICED JAPANESE WHISKY
Cult-favorite Japanese whisky bottlings have been seeing astronomical price increases recently, but the more affordable spirits in the genre are perfect for highballs, which also happen to be Japan’s most popular cocktail. Introduced last summer, Suntory Toki ($40) is a blend of grain and single malt whiskies formulated specifically to work well with club soda and carry a reasonable pricetag that’s pretty easy to find just about anywhere. Bourbon lovers should look for Nikka Coffey Grain ($70), which is made from corn and offers a light and sweet profile that’s only amplified in a highball. And Hibiki Japanese Harmony ($65) is another great option, offering intense and complex notes of citrus, fruit and a hint of smoke thanks to its blend of ten different whiskies made at three different distilleries and aged in five different types of casks.


LIGHT-BODIED MEZCAL
Some mezcals need to be paired with strong flavors to make a balanced cocktail, but the lighter and cleaner-flavored ones are incredible with club soda, which brings out their smoky, grassy and citrusy notes. (Luckily, these also tend to be less expensive than their more assertive cousins.) Don Amado Rústico ($50) offers subtle smoke and nice peppery spice, as well as seriously old-school production methods: It’s distilled in tiny clay pot stills from estate-grown agave. Alipús San Juan del Río ($50) is made from the same type of agave as Don Amado Rústico, but it has a much fruitier flavor and pleasant sweetness. And the new-to-the-US Bozal Ensamble ($50) is made from a mix of three different types of agave, all of them growing wild. Its herbaceous and floral notes make for an amazingly refreshing highball.
GENTIAN LIQUER
Gentian is an herb native to the mountains of Europe and Asia whose extremely bitter root has been used as medicine for thousands of years. It’s also the base for a long list of liqueurs that make for delicious, refreshing aperitifs. Campari ($28) is definitely the best-known in the category, with a seriously intense bitter-and-sweet flavor that becomes bracing with club soda (plus, its signature bright-red color turns an appealing pink). Suze ($28), made in France, isn’t quite as bitter as Campari but offers an assertive herbalness that goes well with grilled veggies (or, hell, a hot dog). And Salers Aperitif ($20) is the among the oldest members of the category, produced since 1885. It’s somewhat less sweet than the other two, with a nice earthy bitterness that’s very palate-cleansing.

UNUSUAL AMERICAN GIN
If you’re a Martini drinker, try a gin and soda next time it’s hot out and you’ll be converted. In a highball, a heavy-on-juniper gin can be overwhelming, so your best bet is one of the new crop of American gins using more unusual ingredients and techniques. St. George Terroir ($35) is one of three gins made by the pioneering Northern California distiller, and it’s focused on native botanicals from the Golden State like Douglas fir, bay laurel and sage, making for a lovely savory highball. Washington D.C.’s Green Hat Spring/Summer ($36) has cherry blossom and rosemary flavors that are an ideal taste for a hot day, so much so that the formerly seasonal release is now available year-round. And Philadelphia’s Bluecoat Barrel Finished ($35) ages a fairly juniper-forward gin in new American oak for three months, which mellows the piney notes and adds flavors of toffee and caramel.


AROMATIZED WINE
For centuries, winemakers have been spiking their products with distilled alcohol and adding herbs and spices to create a variety of cocktail-friendly products, and these lower-alcohol bottles are a great choice for summertime day-drinking. The most common style of aromatized wine is vermouth, and Carpano Antica Formula Vermouth ($30 for one L) has long been a bartender favorite. It’s sweet and fruity for sure, but with a backbone of root-beer spices and vanilla that make it as at home in a Manhattan as in a highball. For a lighter aperitif, turn to Cocchi Americano Bianco ($20). Made in a similar way to vermouth (but using gentian root instead of wormwood as the main botanical, which makes it an americano instead), Cocchi Bianco is based on moscato wine and has a nice balance of fruity, spicy and bitter notes. Or you could go all-American with Brovo Pink Vermouth ($20), based on a rosé made from Washington State-grown pinot noir grapes. It’s light but luscious, and adding bubbles makes it all the more summery.