Quote Originally Posted by kuri
i'm with sensisuperskunk here. i learned that first hand that rock wool can become overly saturated and then can cause ROOT rot if it is saturated for too long. first hand knowledge there. learned the hard way. my opinion is do not let rock wool sit in water or not water every day. it will take an easy three days at least before the rock wool comes to a dangerous dry state.
Kuri-


I disagree, but all is a matter of opinion...it does however recommend that you do not let the grodan sit in water. That is the point...you don't need to let it sit in the water as it retains moisture. When you have seedlings under a humidity dome it isn't wise to have water in the tray anyway. I only spray my seedlings when I spray the humidity dome. Also, I have had rockwool dry out in a day or less in high humidity conditions. So, the three days thing isn't probably the best rule. All a matter of opinion I guess...
willybblue Reviewed by willybblue on . Rock wool dampness During seedling stage, should the rockwool be kept wet, or let to dry between waterings? How about after veg starts? I had a 1 inch blueberry that died overnight and the wool was dry. PH was around 5.8 and using miracle grow for the seed stage. Any help? Thanks! Rating: 5