Seed Germination

Large seeds can be planted directly into aggregate culture systems or devices such as the Pipe Dream and thinned later. Plants with small seeds should be transplanted into the system to insure a good stand. With the water culture method, all plants must be transplanted to the system.

Seedlings to be transferred can be grown with their roots exposed or in root cubes. It is best to grow them with exposed roots if they are to be grown in a water culture or aeroponic system. Sow the seeds in quartz sand, coarse vermiculite, or perlite. Water them and cover them with wet paper towels or cheesecloth until they germinate. Then remove the covering and thin the plants. Moisten them as needed with a dilute nutrient solution rather than water because the germination medium does not provide adequate nutrition. A one-fourth concentration of the nutrient solution recommended in the next section may be used. When the seedlings are large enough to transplant, gently wash the growing medium from their roots. Do not be concerned if a few pieces of the medium remain on the roots.

Seedlings for the PVC pipe or NFT system should be grown in sterile root cubes, which are composed of expanded plastic foam, cellulose fiber, or a compressed mixture of peat and vermiculite. These cubes provide weight and help support the plant in the tube. Peat-lite mix or peat pots should not be used as they will disintegrate, and the particles may clog the pump that circulates the nutrient solution. Oasis Rootcubes and Horticubes are examples of commercially available root cubes.