Build A Hydro Garden
The Aztecs and Incas amazed the Spanish conquistadors with their floating gardens, and now 500 years later you can impress your friends and neighbors with yours. A floating hydroponic garden is easy to build and can provide a tremendous amount of nutritious vegetables for home use, and best of all, hydroponic systems avoid pest problems commonly associated with the soil. This simple guide will show you how to build your own floating hydroponic garden using material locally available at a cost of about $40.00
Construction Steps
1. Many simple containers can be used to make a floating garden. Examples include: kiddie pools, small plastic storage containers, trash cans, and buckets. Many shapes and sizes of containers will work, but they should be able to maintain a 4-6 inch depth of nutrient solution for the best success.
2. Place a sheet of 1 1/2 inch thick styrofoam insulation in the lined frame. Make sure the edges have sufficient room to allow the garden to move up and down. The styrofoam sheet will create a floating platform in the frame.
3. Fill the water garden with water to a total depth of at least four inches. Keep track of the total gallons of water you add.
4. Add water-soluble fertilizer, such as 20-20-20 with micronutrients, at a rate of 2 teaspoons of fertilizer for each gallon of water used in the water garden. In addition, add Epsom Salts (magnesium sulfate) at a rate of one teaspoon for each gallon of water. Use a soft broom to mix the water & fertilizer in the garden or premix all fertilizer in a bucket before adding to water garden.
5. Light rainfall will have little effect on the water garden; only extensive flooding would require fertilizer adjustment based on the amount of water added by rainfall. The solution in the garden needs to be replaced periodically for optimum production. You can grow two crops of salad greens in the same solution before changing the entire solution and starting with a new batch.
6. Use a hole saw or sharp knife to cut holes in the styrofoam. The hole size should allow the bottom of a foam cup to be 1/8 inch below the underside of the styrofoam tray. It is very important that once foam cups are placed in the holes, they do not extend down lower than 1/8 inch below the bottom of the styrofoam sheet! This allows the root mass to wick up water without being totally submerged, which might lead to drowning of the root and plant death.
7. Optimum plant spacing for most plants would be 6 inches from the sides and apart.
8. Transplants used in this system should be grown to be fully rooted in a typical soilless media. Transplants can be grown at home in many root ball shapes in a loose media, purchased from garden suppliers, or grown in compressed peet pellets.
9. Place young starter transplants directly into the cups. Use toothpicks, if desired, to hold the transplant in an upright position. Do not remove the potting soil from the transplant.
10. After placing the young transplant in the net pot or styrofoam cup, do not add any potting mix or other material around the young transplant as this will keep the roots too wet and inhibit oxygen intake.
11. Add extra water and fertilizer as needed to keep the styrofoam sheet floating on a minimum of 4-inches of solution.
Crops
Several leafy salad crops grow well during the cool season. There are fewer crop options for the warm season, however, basil and some cut-flowers, like Zinnia and sunflowers have done well. Other crops you could experiment with are watercress, cucumbers, herbs, and some flowers. For example, watercress grows very well, and periwinkle does not grow as well in a floating garden.
New Research
Ongoing research with plants such as tomatoes in floating systems indicate that larger plants require more above-water rooting volume (more air-space) in order to produce successful yields. To produce more root mass above the water, you may want to test a system that uses two stacked styrofoam floats with holes drilled in the bottom one and all but a six-inch edge around the perimeter cut out of the top one. Fill the empty top float with perlite, vermiculite, or other hydroponic media and plant vegetables or flowers into it the same way you would plant a normal garden. Preliminary results show this method to be promising if starter fertilizer is used on the young plants until their roots reach the fertilized hydroponic solution below the floats.
Additional Resources
For more information on hydroponic production, please visit the website www.nfrec-sv.ifas.ufl.eduwww.nfrec-sv.ifas.ufl.edu Videos may also be purchased for $15.00, plus tax, by contacting the IFAS Bookstore at (352) 392-1764 or online at www.ifasbooks.ufl.edu
