Rockwool Starter Cubes have a uniform density, firmness and fibrous structure. This means that distribution of water, nutrients and pH level are also uniform, which results in a beneficial effect on germination. The fibrous structure of the cubes means they are resilient and will not fall apart. They will retain their shape during soaking, seed germination, rooting of cuttings and transplantation into larger rockwool cubes and hydroponics systems.
The rockwool starter cubes we sell are the larger size on the market – 1.5 inch (36 mm). They are suitable for transplanting into the larger hole 3” or 4” rockwool blocks which ca then go into your system. Rockwool starter cubes are available as a tray of 24, 77 or a box of 18 trays.
What are Rockwool Starter Cubes made from?
Rockwool is made by exposing rock minerals to extremely high temperatures and then spinning to make fibres. This then goes into a mould to make blocks and slabs of varying sizes. The advantages of using rockwool as a growing medium are that it can retain a great deal of water for the plant. It’s fiberous nature means it can hold plenty of air too, to supply the roots with oxygen. Rockwool starter cubes are alkaline so before use they need soaking in water adjusted to a pH of 5.5 to ensure optimum acidity. Don’t squeeze out the cubes as it can damage the structure, making it less effective.
Trays of 77 rockwool starter cubes fit snugly into the large budget propagators sold at Straight Up hydroponics. If you require heat to assist germination or rooting, we advise using a propagator heat mat. To get the very best from your seedlings or cuttings, consider a T5 propagation lighting unit and a Cloning tent. All of the propagation products are on our website and you can see them by clicking here.