Apples, like the colors of autumn leaves, have their own season of perfection. Most apple varieties ripen from late summer into early fall. You can tell an apple is ripe and ready for picking by its color, smell, and texture. Generally, ripe apples have a vibrant color and a sweet, fruity aroma. If the apple is firm but gives a little when pressed, it's a sign of ripeness. The ultimate test, however, is the taste — a ripe apple should be crunchy, juicy, and bursting with flavor. Remember, different apple varieties have different harvest times and visual cues for ripeness, so it's helpful to familiarize yourself with the type of apple you're using for your homemade soda.