Pretreat the rockwool!
Rinse the rockwool a few time under tap water.
Get rid of the excess water by holding the cube loosely in your hand and flick the wrist. The weight of the excess water will come out of the rockwool by doing this. Never squeeze the water out of the rockwool, it will crush the vital air pockets in the cube.
Soak the cube overnight in pH5.0 water (bottled water would be perfect).
Next day, flick all water out of the rockwool cube until the cube is just damp and moist.
(It would been easier to let the taproot grow a half inch or so)
Poke a hole in the middle of the rockwool. Enough for the taproot to drop into it without damaging it.
Place the taproot in the hole, with the seed shell above the rockwool, gentle pack the taproot into the rockwool, to not let dry air at the taproot.
Cover the cube with a clear plastic cup or tuberware container, anything that is clear to let light in and to keep the humidity high.
Keep the seedlings warm, around 26c.
Only water the cube by dipping the bottom 2mm or 3mm of the cube in plain pH5.8 water (and H202 if available) for 1 or 2 seconds. The cube will wick the water up to the seedling, air pockets in the rockwool cube will allow oxygen to the roots.
Rockwool has to be only damp, not saturated in water. If saturated, the cube will become waterlogged and starve oxygen from the roots.
Hope that helps.
