I grew up in South Florida amid a jungle of tropical plants and fruit trees. My father was an avid gardener and collector of palm trees. Our backyard was full of bananas, citrus trees, and flowering vines. This is where I first became intrigued with different types of lush foliage plants. Fairchild Tropical Botanic Gardens contains a huge collection of unique tropical plants. Set around natural water features and the beautiful Florida sunshine this garden is particularly great to visit during the winter months.
Located in Coral Gables, Florida it is 83 acres of tropical plantings. Various garden collections surround large lakes with an occasional napping crocodile. Founded in the late 1930's by plant collector Robert Montgomery who named it after the plant hunter Dr. Fairchild. There are many large specimen trees planted by Dr. Fairchild still . 
growing in the gardens. There is a very large, impressive African Baobab tree planted by Fairchild.
The gardens have evolved a lot in the years since my first childhood visits.The glass artist Dale Chihuly had many works there in the early 2000. The gardens were even more exotic looking with glass orbs floating in the lagoons. I love all the different collections but my favorite area is the large lake surrounded by stately palms. It was one of my favorite parts of the garden to photograph in my early career as a photographer.
Another site to see in South Florida is not technically a garden but well worth the trip. Coral Castle in Homestead Florida always fascinated me as a child. How did Edward 
Leedskalnin move those giant coral rocks into position? He took his secret to his grave but he often told people he knew the secrets of the builders of the pyramids.The rocks are softened by lush tropical plantings of bougainvillea and other colorful flowering plants. There are even blooming pineapple plants set among the rocks.
The Redland's Fruit and Spice park is also worth a visit. It is not a flashy garden but for any herb gardener it is very informative.