For the ginger starter: In a sanitized quart-size glass jar, combine the ginger, sugar, and water. Cover with cheesecloth or a clean dish towel and secure with a rubber band. Place the jar in a warm, dark place out of direct sunlight for 24 hours.

After 24 hours, the starter may have small bubbles or look the same. Feed the starter by stirring in 1 teaspoon finely grated fresh ginger and 1 teaspoon sugar once a day for 7 to 10 days. When the mixture is bubbling undisturbed, it's ready to use.

For the ginger beer: In a sanitized glass jug or other non-reactive container, combine 1 cup of the ginger starter, the water, sugar, lemon juice, and ginger. Cover with cheesecloth or a clean dish towel and secure with a rubber band. Place the jug in a warm, dark place out of direct sunlight for 8 to 10 days, stirring the ginger beer twice a day and tasting for sweetness. Add 1 tablespoon sugar maximum per day if needed.

When white natural yeast appears at the bottom of the jug and the ginger beer bubbles when you stir, it's done with its first fermentation.

Transfer the ginger beer to clean bottles with tight-sealing lids. Seal the bottles and store in a dark room at room temperature (70°F to 75°F) to ferment for 2 days. If it's too warm, the ginger beer will need less time to ferment and might explode if left unattended for too long. Move the bottles to the refrigerator and consume within 3 days.