Starter cubes, used by hydroponic growers, as well as soil gardeners, are comfortable growing media for starting seeds. Made of inert material, starter cubes provide perfect support to the plant and its rhizomes. The cubes are capable of retaining water, but they do not supply a plant with any nutrients, unless the latter are dissolved in the water. Nowadays, there are 4 types of starter cubes: Organo-Cubes, Oasis cubes, Rockwool and “peat pots”. The most popular among the gardeners are the first three kinds of cubes (Organo-Cubes, Oasis cubes and Rockwool), while “peat pots” lose their popularity due to their tendency to accumulate too much water, which can spoil the seeds and the seedlings. Oasis cubes, Rockwool, and Organo-Cubes, on the other hand, retain water along with enough air, which prevents the medium to be too moist.
Preparing hydroponics starter cubes for the use depends on the type of the cube you have. For example, Organo-Cubes are ready for use, while Oasis cubes and Peat pots should be soaked in water (with pH adjusted to 6 – 6.5) before use. As soon as the cubes are saturated with water, they should be left to drain a bit, and then they are ready to be used. Rockwool is different, since it has high pH. Therefore, it should be soaked in water with pH adjusted to 5.0 in order for this acid solution to be balanced to the pH level required for the plants normal growing. These cubes should be soaked in water approximately for 24 hours, followed by the drainage prior to the use.
Having done these easy manipulations, the seeds can now be planted. Small holes about ¼ to ½ inch deep should be made in the cube with a tip of a pencil or a pen. Then seeds may be put into the holes and covered with some cube material from around those small openings.
It is best to keep the seed cubes moist, but not wet, always preventing them from staying in the water. The cubes do not need light until the seeds germinate. Similarly, no nutrients are necessary for the plants until they have their first true leaves developed. In this case a diluted nutrient solution
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