It is possible to grow hydroponic blueberries, even in the warm Florida climate. You can easily build a basic hydroponic system that won’t cost much and will be simple to use. Two kinds of blueberries do well in Florida: the southern highbush (hybrids of Vaccinium darrowii, Vaccinium corymbosum and Vaccinium virgatum), hardy in U.S. Department of Agriculture plant hardiness zones 7 through 11, and the rabbiteye blueberry (Vaccinium virgatum), hardy in USDA zones 7 through 9. Only the low-chill cultivars of those blueberries should be used because they have a minimal chill period requirement for fruiting. Southern highbush blueberries are better than rabbiteye for container use because they are smaller, according to the University of Florida IFAS Extension website.
Cut two small notches in the top of one end of an opaque, plastic, 18-quart or larger bin, using a box cutter for the task. One notch needs to be large enough to hold an electrical power cord and the other notch large enough to hold 1/2-inch plastic tubing. Space the notches 3 inches apart. This bin will be used as the hydroponic system's reservoir
Drill two 5/8-inch-diameter holes in the lid of the bin, or reservoir. Place one hole near the center about 6 inches away from the end at one edge of the lid and the other hole in a similar spot at the other end. The holes will allow drain tubes to pass into the bin.
Place the reservoir on a low shelf or other suitable location near an electrical outlet. Setting your system outside in a protected area will allow you to grow your blueberries without the use of artificial light.
Drill a 5/8-inch-diameter hole in two 5-gallon buckets, making the hole about halfway between the edge and the center of the bottom. Place a 5/8-inch-diameter bulkhead fitting into each bucket's hole, and screw the fittings down snugly. Lay a 3-by-3-inch piece of fiberglass screen over the fitting on the inside of each bucket. The screen will prevent clogs.
Connect one 2-foot-long section of 5/8-inch-diameter plastic tubing to the fitting of each bucket. Fill the bottom one-half of the two buckets with expanded clay pellets or sterilized pea gravel. The material needs to be heavy enough to support an adult blueberry plant and its fruits.
Set one bare-root blueberry plant in each bucket. Fill the area around each plant with additional clay pellets or pea gravel so that the roots are completely covered. Do not cover the stem of either plant.
Place the buckets on a shelf or other suitable support near the reservoir. The buckets must be high enough above the reservoir to allow gravity to drain the nutrient solution from the buckets each time they fill. Let the bulkhead fittings hang over the edge of the shelf, or drill a hole in the shelf so the bulkhead fittings extend through and below it.
Attach a 2-foot-long section of 1/2-inch-diameter tubing to the output nozzle on a submersible pump. Place the pump in the bottom of the empty reservoir. Feed the tubing through one of the notches at the top of the reservoir and the pump's electrical power cord through the reservoir's other notch.
Split the output from the pump into two tubes by attaching a plastic Y piece that is 1/2-inch diameter to the 1/2-inch-diameter tubing you attached to the pump's output nozzle. Attach one 2-foot-long section of 1/2-inch-diameter tubing to the two upper portions of the Y.
Fill the reservoir to within 3 inches of its top with water. Mix in a commercial nutrient solution with the water according to the nutrient manufacturer’s directions. The exact measurements to use depend on the brand of nutrient solution.
Test the pH level of the water-nutrient solution mixture in the reservoir with a pH test kit or pH meter. The pH level should be 4.0 to 5.5. If it is not, then adjust it using the appropriate chemicals supplied in a pH adjustment kit, following the kit's instructions.
Clip one output hose to the top of each bucket with a hose clip so that the water-nutrient solution mixture will flow into the buckets when the pump is turned on. Put the lid on the reservoir, and place the end of each bucket's drain hose into one of the holes in the top of the reservoir's lid. Set a digital timer so that the pump will fill the buckets three or four times per day. Plug in the timer to start your hydroponic system.