Harvesting vegetables from a hydroponic garden in your basement is a sure way to brighten a winter day. Once you construct a hydroponic grow box, set yourself up for success by growing a crop that is well-suited to this setting, such as leaf lettuce, spinach or Swiss chard. These plants, along with several types of herbs, tend to require less direct sunlight and prefer cooler temperatures, making them ideal for basement growing.
Cut 1 5/8-inch holes (or the size needed for your net pots) in the top of the Styrofoam box lid. Cut the holes 2 or 3 inches apart. Put the lid on the box.
Set net pots in the holes you have cut, leaving one open for pouring water into the system. Fill the net pots with dampened potting mix and sow two to four seeds in each pot.
Select a location for your hydroponic vegetable garden, such as your basement or another area away from direct sunlight. Screw two hooks into the ceiling the appropriate distance apart to hold the fluorescent light fixture. Hang a length of chain from each hook.
Set a table in place below the hanging chains and put the grow box on the table. Wire the fluorescent light fixture to the chain so you have light 4 inches from the net pots in your grow box. Hook the programmable timer to the light following manufacturer's directions. Put the bulbs into the fixture and plug it in. Program the timer to provide 12 to 14 hours of light per day.
Fill your grow box with water until water touches the bottom of the net pots. During the course of growing vegetables, keep the water level so that is it always touching the net pots, but make sure to leave air space between the water level and the lid.
Add fertilizer to the water in the grow box after your vegetables are up and have their first true leaves. Use a standard water-soluble fertilizer such as a 15-15-15 formula, following directions on the label.
Watch your vegetables grow and move the light up as they do so to maintain a distance of 4 inches from the tops of the plants to the light.