Thespis420

I'm thinking for my next garden I'm going to use passive hydro. However, I keep hearing mixed ideas about this. THIS website's grow guide highly recomends setting rockwool cubes directly in a reservoir filled with a water /nute solution. I guess the rockwool holds enough oxygen so that it doesn't become saturated with water and drown the roots. Is this correct? Other people on this site keep saying don't put your medium directly in the water because you'll get root rot. Does this include rockwool. Any help would be greatly appreciated.

lilbuddie

I used that method before and if you are not careful you can get root rot easily but it can be done successfully. You can add Oxygen Plus plant food to help add CO2, Or use H2O2 Or use an air stone a pump to keep oxy circulating over the roots. I haven't used rockwool before but I can see where that would happen quickly at the bottom of the cude where it would be water logged all the time. I was using a 50/50 perlite / vermiculite mix with the bottom 2" of the conatiner with perlite only and the OXY Plant food. I got through fine without any root rot but you have to be very careful of the roots if there are growing out from the bottom of the pot you don't want to break them off. Also, it gets to be a pain in the butt to swap out and change the trays that hold the solution. You need to do this to avoid salt build up. Also, it gets harder to switch out the trays when the plants get big.

Good Growing
LB