Maybe you put the seed in the rock wool upside-down ? With the tap root pointing skywards ?

If the seed was shallow enough the tap-root would grow upward out of the rock wool and then begin to turn downwards.

just an idea.

Take care
silent leprechaun Reviewed by silent leprechaun on . Basic question about germination / seedling stage. I recently germinated my seeds and have planted them in a rockwool like little squares (i think the material is actually coconut shredding or something) if the white "tail" that starts to grow is sticking up in the air out of the rockwool is this bad, will the roots grow properly ? Do i need to replant the "seedlings" deeper in the rockwool so the whole white "tail" is burried. Thanks for the help -D.A. Rating: 5