Growing cabbage hydroponically is an easy way to have a fresh supply year-round. The flavor and nutrient value of hydroponic grown cabbage is the same as cabbage traditionally grown in soil. Purchase a hydroponic grow system from a local garden center, online supplier or build your own. You can purchase cabbage seedlings from a nursery or start seeds directly in your hydroponic grow system.
Choose the location for your hydroponic garden. Install grow lights to ensure enough light is available year round for your plants. Set up your hydroponic grow system. Place the water tight containers on a sturdy table that is near a GFI (ground fault interrupt) outlet. Install grow lights so that they hang over top the hydroponic grow system.
Insert one to two seeds in a grow cube. Place the grow cube into a small net pot and insert into the hydroponic grow system. Seeds should sprout in seven to 10 days. When the seedlings reach two inches tall, they are ready to transplant into large net pots.
Remove seedlings from their pots. Plants purchased from a nursery require that the roots are washed gently with cold water to remove all soil. Place the seedlings in tall net pots and place in the hydroponic garden.
Monitor the pH balance of the hydroponic grow system; it should be 6.5. Add grow medium (nutrient content) every three weeks to the grow system. Drain water completely every three weeks. You can begin harvesting cabbage in 60 to 90 days depending on the variety.