this sounds so cool, but not as possible for everyone to do. There are islands and there are ways to live off of land. You could live on a lake on a floating mat that can be used for gardening to.
Some ancient south central americans did. They weaved mats and floated them and grew food on them and even lived on them.
The Floating Gardens of the Aztecs
In the 11th century, The Aztecs of Central America, a nomadic tribe that was driven onto the marshy shore of Lake Tenochtitlan in the central valley of what is now Mexico, practiced hydroponic growing methods out of necessity. Without land to grow plants, they were forced to learn other ways of producing crops. Being a very ingenuous people, they built rafts out of rushes and reeds, lashing the stalks together with roots. They dredged up soil from the shallow bottom of the lake and piled it onto the rafts.
Chinampas
Floating Rafts of the Aztecs
Soil was taken from the bottom of Lake Tenochtitlan and placed on the rafts which were made of reeds, rushes and weeds. The soil was rich in organic debris which provided nutrients to the plants. Plants were placed on top of the soil. The plant roots grew through the soil and down into the water be- low. Some of the Chinampas were as long as 200 feet, growing vegetables, flowers.
Because the soil came from the bottom of the lake, it was rich in organic debris that held nutrients necessary for plant growth. Vegetables, flowers and even trees were grown on these floating rafts, called Chinampas. The plant roots would grow through the mats and down into the water.
The Chinampas were sometimes joined together to form floating islands as large as 200 feet long. Some Chinampas had a resident gardener who harvested and sold the vegetables and
flowers on the raft.
Ah, here I found a site that explains it a little.
"As the Aztec village became huge, so did their floating gardens.
During the invasion of the Aztec villages by the Spaniards in the 16th century. these floating gardens were witnessed and documented. Such an innovative, yet productive plant growing system must have shocked the invaders.
Use of the Chinampas, or floating gardens, continued into the 19th century and some remnants can still be seen in Mexico today. "
http://www.hydroponicsonline.com/lesson ... istory.htm