Growing lettuce in a hydroponic system is an easy way to have fresh lettuce year round, especially if you have little space for a garden. The nutrient value and flavor of hydroponically grown lettuce is similar to that of lettuce grown in a traditional garden. Hydroponic garden systems can be purchased online or at most local garden centers and are simple to set up.
Set up your grow system in a permanent location. You will need grow lights to make sure there is enough sunlight available for your plants, even if you are using a green house.
Place one seed in each grow cube. Insert the grow cubes into the tray that comes with your grow system. Lettuce seeds should germinate in seven to 10 days. When the seedlings are 2 inches tall, transplant into net pots. Add 1 teaspoon of grow medium to the water supply
Check the pH balance of the water system; it should be around 6.5. Nutrient content (grow medium) needs to be added every two weeks to a hydroponic grow system. The water needs to be drained completely from the system every three weeks. You can begin harvesting lettuce in six weeks for "baby" lettuce, eight weeks for mature lettuce.