Vegetables grown in a hydroponics system create an indoor garden for produce harvest throughout the year, even during the winter months. Planting vegetable seeds in rockwool is a quick and easy method of starting plants for transplanting directly into the hydroponics system. Rockwool is a soil-less material made from rock and sand fibers spun into a cube shape. The cubes create an optimal environment for plant production by holding water and air around the plant roots. Vegetable plants that grow well in a hydroponics system are tomatoes, peppers, cucumbers and lettuce.
Prepare the 1-inch rockwool cubes by soaking them for two hours in a planting tray filled with water. Empty excess water from the tray and line the rockwool cubes neatly in the tray for planting.
Sow one seed into each cube to a depth of 1/8 to 1/4 inch. Verify preferred planting depth on the seed packet for increased germination rates.
Cover the tray with clear plastic to create a greenhouse environment for seed germination. Set the tray in a location that receives indirect sunlight and has a temperature of 68 to 70 F.
Monitor the rockwool cube moisture each day during the germination process to prevent them from drying. Spray the cubes with water as needed.
Remove the plastic cover when the seed sprouts appear. Move the tray to an area that receives full sunlight and continue to grow the seedlings until they reach 2 to 3 inches in height.
Mix a solution of hydroponics nutrient water according to the package instructions. Mist the rockwool cubes with the nutrient water each day from the time the sprouts appear until transplanting the seedlings.
Transplant the rockwool cubes into the hydroponics system once the seedlings are 2 to 3 inches in height. Place the 1-inch cubes inside larger rockwool cubes that are set into the hydroponics system. Do not remove the seedlings from the small cubes.