As with tomatoes, the trick to growing peppers for cocktails is to choose a variety that is small enough to fit in the glass as a garnish. It’s also important you actually like the pepper; there’s no point growing hot peppers if you can’t stand spicy cocktails.
A good hot pepper variety to try is ‘Peguis,’ a heavy producer of large, green jalapeño-style peppers. For sweet peppers I like ‘Cherry Pick,’ a small, round, red pepper that matures early, making it a good option for chilly summers like I have in northern California.
In any case, give peppers full sun and protection from the wind. If the summer gets off to a slow start, you might even consider giving them a little shelter behind a cold frame. Even using an old glass window as a lean-to to above the pepper plant can give it a little extra shelter and warmth. Like tomatoes, they need rich soil amended with plenty of compost, a granular organic fertilizer formulated for vegetables, and regular water. Uneven watering in temperature swings can stress the plant out and keep it from blooming or producing fruit.
I use slices of peppers in a lot of vodka, gin, and tequila drinks, and I’ve found the flavor to be pretty stable in infused vodkas. Don’t go overboard with the heat, however. Even if you love spicy drinks is much as I do, an incredibly spicy infused vodka can just be overpowering. Dial it back a little and add extra spicy pepper when you make the drink if you really want it.