Unlike other fruits, avocados do not ripen on the tree. According to Avocado Central, growers pick the fruit while still hard and let the ripening process occur during shipping to the market. These hard avocados take time to ripen before you can enjoy them, but some methods encourage faster ripening. These methods expose the avocado to higher levels of ethylene gas, naturally released by fruit as it ages.
Place avocados into a brown paper bag with an apple or banana.
Fold over the top of the bag to close it.
Store the paper bag at room temperature for one to three days or until the avocados yield when gently pressed. Opt for this method over the three to six days of ripening required for avocados placed alone in the paper bag.
Transfer the ripened avocados to the vegetable crisper drawer of your refrigerator for up to two weeks, according to What's Cooking America.