For each cocktail
Add sugar to a mixing glass and fill with ice. Pour lime juice and gin over ice and stir well. Strain into a rocks glass with a large ice cube in it. Add lemongrass and lemon and serve.
Using a chopstick or a knitting needle as a guide, stuff lemongrass, herbs, and citrus peel down the neck of the gin bottle. Seal and let stand a week or more until the gin has a turbo lemon-botanical flavor.