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Welcome to the fascinating world of hydroponic gardening. The following instructions will guide you through the process of preparing starter cubes, planting seeds as well as mixing and using nutrient solutions.

Starter cubes are an easy way to start seeds. They are used by hydroponic growers and soil gardeners as well. Starter cubes are made of an inert material, that is a material that doesn’t provide anything to the plant other than as a support for the plant and it’s roots. The material retains some water but doesn’t supply any nutrient (unless nutrient is dissolved in the water. There are basically 4 kinds of starter cubes: Rockwool, Oasis cubes, Organo-Cubes and "peat pots". The types most favored are rockwool, organo-cubes and Oasis cubes. Peat pots are losing favor among gardeners because they have a tendency to retain too much water and as a result can "drown" the seeds and seedlings. Organo-cubes, rockwool and Oasis cubes retain water well but also retain enough air so that the medium doesn’t stay too wet.

Preparing the starter cubes varies with the kind of starter cube you are using. Organo-Cubes come ready for use. The Oasis and Peat pot cubes should be pre-soaked with water that is pH adjusted to 6 - 6.5. The cubes need only to be saturated and then allowed to drain. These cubes are now ready to use. Rockwool has a high pH. As a result they must be treated differently. With Rockwool the cubes must be pre-soaked with water that is pH adjusted to 5.0. This low (acid) pH solution will balance the overall pH to a level that plants require. The cubes should be soaked for about 24 hours. Then drain the cubes, they are now ready to use.

Once the starter cubes are prepared you can plant the seed(s). Using the tip of a pen or pencil make a small hole in the top of the cube aprox. 1/4 to 1/2 inch deep (if there isn’t one already). Place the seed(s) into the hole and gently cover the seed(s) by packing some of the seed cube material from around the hole over the seed.

The seed cubes should be kept moist but not wet. They should never be allowed to sit in water. The cubes will not require light until after the seeds sprout. The plants don’t require any nutrient until they have formed their first "true" leaves. When they develop the first true leaves you can start giving them a diluted nutrient solution (1/4 to 1/2 strength).

The nutrient solution is simply water with fertilizer dissolved in it. To prepare the solution you start with good quality water and then mix in the fertilizer at a rate prescribed by the fertilizer manufacturer. The pH of the nutrient solution is important and must be checked and adjusted (if necessary) with liquid pH adjusters. The pH requirements of the nutrient solution is determined by the type of plant you are growing but a good "rule of thumb" for setting the pH is between 6.0 - 6.5 for all growing mediums except rockwool which requires a pH of 5.5 to 5.8. For young plants you need to mix a nutrient solution that is 1/4 to 1/2 of the "full strength" mixture that the fertilizer manufacturer suggests. After the plants are two weeks old you can then start using full strength nutrient solution. You want to keep the growing medium moist (but not saturated) with the nutrient solution.

Once the seedlings have grown roots out of the starter cubes it is time to transplant the plants. This is simply a matter of placing the plant and starter cube into or on top of your permanent growing medium. This growing medium can be any hydroponic growing medium or even soil.