I was using Fox Farms Grow Big, which has .6% Mg but no calcium. I transplanted them, because they were too big to be in small rockwool cubes. I suspect this was the problem. For various reasons, they stayed in the clone tray for too long.
Thanks for the input though. Does anybody have any...
Hi all,
I have a dozen clones in the same tray, and a few of them are getting brown spots on their leaves. They get a weak mix of Fox Farms Grow Big after a few weeks when they're well rooted. The ph seems okay, according to me cheap-o test kit. The problem only occurs on a few of the clones...