Whats going on leaves....rotting? HELP

My leaves seem to be rotting, only on 1 of 6 plants but leaves on other plants seem to be yellowing a little bit, please help what'd I need to change?
I plant in soil, use 400watt HPS bulb humidity seems to be ok it's at 56% or so and temp is at 75.2 degrees Fahrenheit when the light is off.
Here are some pics,
I am feeding it some miracle-gro nutes, could it be nute burn?

What kind of soil?

kizzzzurt said:

What kind of soil?

Click to expand...

Miracle-Gro

Got any perlite in there? I'm thinking that it's your soil.

Overwatering? Anyone else get that gist?

kizzzzurt said:

Got any perlite in there? I'm thinking that it's your soil.

Overwatering? Anyone else get that gist?

Click to expand...

Nope I have no perlite in there at all, I'll pick some up tomorrow if that's the problem. I'll make sure I don't water it as much as I do now too just to make sure that's not the problem.
Thanks for the quick reply!

I would guess a combo of overwatering and nute burn. It seems Miracle Gro is tricky for MJ plants. It has nutrient pellets that release their contents in bursts which is what roses prefer while MJ plants prefer a steady slow supply. When you water them, the pellets release and can overdose the plants. There are some tricks to dealing with MG soil. I think Cranker has a guide to growing in MG.

This is just what I have picked up from browsing the forums. I've never used MG soil.

You are doing what most new growers do. Over feeding.
The way I understand it is Miracle grow potting soil comes in a couple different mixes, the standard and time release nutrients. Both have too too many nutrients for seedlings but the time release type releases even more nutrients when watered. Depends on the strain or I should say the phenotype of the strain as to how much they can take.

There are a lot of people who use it by itself but I think Miracle grow is fine at the bottom of the pot or mixed at about 1/2 strength.

Ok, I'm going to water it alot less now, thank you all!
If it does notsolve the problem then I'll try dilute the nutes even more then i already do, here are the nutes that I use, http://www.diy.com/diy/jsp/bq/nav.jsp?action=detail&fh_secondid=10277587&fh_location=//catalog01/en_GB/categories%3C{9372012}/categories%3C{9372020}/categories%3C{9372095}/specificationsProductType=plant_care/specificationsSpecificProductType=plant___vegetable_food

Cant find the bag of Mirace-Gro soil that I bought, I'll try to get a picture.

Thanks for all the help guys, Lets hope she can recover from this.
They're 2 weeks old tomorrow!

They dont need any added nutrients right now, if anything just water.