A hydroponic garden grows plants without soil using a nutrient solution to feed plants. Indoor hydroponic growing systems give the gardener control over light, temperature, and plant nutrition---all of which are important contributors to successful crop production. A hydroponic growing system uses a pump to push nutrient solution from a reservoir to the roots of growing plants suspended above the liquid in a pot filled with soilless growing medium. Excess solution drains back into the reservoir after feeding the plants.
Basic Set Up
Fill the reservoir with nutrient solution developed for hydroponic growing. Place the pump into the reservoir and connect an output tube from the reservoir to the plant tray. Connect a drain tube from the other end of the plant tray to the reservoir. Connect a timer to the pump and set it for delivering solution every 30 minutes to one hour depending on the plant's needs. Place the plant tray above the reservoir. Put transplants into pots and insert them into the pre-cut holes above the plant tray allowing the plant's roots to dangle down into the plant tray through holes in the side or bottom. Fill the pots with growing medium.
Some hydroponic systems add an air stone into the reservoir to add oxygen. Others rely on oxygen from the nutrient solution.
Grow lights are used to supplement natural light in hydroponic growing. The type of grow light required depends upon the plants and their stage of development. Use metal halide for early growth stages that need the red light spectrum and high-pressure sodium during flowering or fruiting stages to get the blue light spectrum. The correct height for grow lights depends on the wattage. Grow light timers should be set to ensure that the plants receive 12 to 16 hours of light per day.
Controlling Temperature and Humidity
You need to monitor the ambient temperature of the hydroponic growing area. The correct temperature depends on the types of plants being grown and ranges from 60 to 80 degrees for warm season plants and 50 to 70 degrees for cool season ones. To control the temperature adequately, a hydroponic growing system may require heating, cooling, or venting the area.
Humidity in the growing area should be kept around 45 to 50 percent. Use a monitor to check humidity. If less humidity is needed, use the vents or cooling to remove some moisture from the air. For additional humidity, misters work well.