First, by babies got brown tips/spots round the leaf edges, so I read lots of posts and figured 'nute burn'. I stopped the miracle grow treatment and just carried on with clean water to flush out the excess nutes. Now, they have brown spots in the middle of the leaves and are curling down at the ends. I am watering only when the compost is dry. I have no infestation. I have 'em under a 400W MH lamp on 18/6 for veg. Now I wonder if the latest spots are because of mineral deficiencies. How do you tell the difference. I mean, a spot is a spot isn't it? I couldn't get a good photo, so I drew a picture (attached). This is the first crop I've tried for about 10 years. I thought it was all going so well. Please help.
Another MG tragedy! Here's some pics; http://www.marijuana-seeds.net/Thanks-ThankYou.htm These should help, MG is too 'hot' for mj. If one must use MG :toetap: use a 1/4 of what it calls for, then add a little more if the babies say they need more. This of course is the rule of thumb for all nutes.
Thanks for your help. I figured it could me Mg def so I foliar fed with Epsom salts and that seems to have stopped the problem. My crop is lookin' pretty healthy now. I've started with the nutes again and they're shootin' up. I got a pH meter aswell, just in case of any more probs but I haven't used it yet. This is kinda fun ain't it!