Put an unripe persimmon into a brown paper lunch bag. Add a fully ripe banana or apple to the bag. The fully ripe fruit releases a gas that helps to speed up ripening of the persimmon.
Fold down the top of the bag to seal it tightly. Let the bag sit on the counter at room temperature.
Check the persimmon daily. Take it out once it has reached the desired ripeness.
Put the unripe persimmons into a plastic container. Use an eyedropper to apply a few drops of vodka, rum or brandy over the leaves on top of the persimmon.
Cover the container tightly with plastic wrap.
Set the container on the countertop at room temperature. Take out the persimmons once they have reached the desired ripeness.