The gardens are beautiful but I did not stay very long because it was cold. The park also closed very early because it was closing before sundown, which was at about 17h (5:00pm).
Unlike when you are living in New York, you do not often see taxis in Paris. Although they exist, they are often hard to catch by simply waving your hand. If you want to have a taxi pick you up, normally you will have to call a number to have them pick you up. However, the other night I achieved the unthinkable and was able to flag down a taxi! Luckily, this taxi took a credit card (usually they only accept cash payment) and I was able to get home.