How do you know when your avocado is ripe? Take a peek under the dry little button on the stem end. If it’s green, then you will be rewarded with a perfect avocado. If it’s brown, then you will find a brown mess inside. Also, a ripe avocado will be dark in color that gives slightly when gently squeezed. Store them in the refrigerator only when they are ripe for about a week.