Your plants will hug you for the MH. Will the light fix your slow growth? Probably not unless you had crap lights to begin with.
It is correct that a light will do nothing regarding root development. "Switching soil" will certainly hinder root growth though. If you switched to a good soil from bad....and they don't die, your plants will start taking off as long as the roots were not too damaged along the way.
Transitioning from one light source to another will not stress your plant as long as you are switching from so-so lighting to better. Reversing this would indeed slow things down.
Okay, I figured since the plants use light to convert co2 into food that it would also help root growth. But yeah, my soil was horrible. You can see in my top pick how nulchy it became after several waterings sifted then fine particles to the bottom. I've heard mulchy soils can be too acidic.
And I have GREAT NEWS!!! There's a grow shop opening in my area (thank God!) And it isn't opened yet, but I know a guy who knows a guy and he made a phone call and I got to go check out all their inventory and pick up a few tthings. They have ffof and everything, and they had the fox farm original (like a red-colored design on the bag) which I am definitely thinking of trying out. For now tho, I picked up a bag of this
which says to mix as 25% of your total soil.
So I took my miracle grow six month feeding bs and sifted it with a screen out of the window, and it gave me a suuuuuuper fine, soft fluffy soil. I mixed it with the dark moist humus and it felt and smelled marvelous
.
I also picked up a bottle of buddha grow, and wanted to give her a try so I added literally 1-2 drops to my spray bottle that I use to water, which is probably about 20 ounces (it said to use 1 1/2 teaspoons for seedlings on the directions).
I transplanted two of them (big boy went down last night, looked like his stem got chewed through just below the surface and when I woke up he was laying down) into my new soil mix, and added an inch more of the hummus for a top layer of my soil, then gave it a few squirts to moisten it up. Already kurly, the little tiny one in the first couple pictures has shown his first new growth in 4 or 5 days, just by being in the new soil with a super low level of added nutes and under the metal halide).
Tomorrow morning will be my true test when I see how Larry is doing. He's basically my only healthy seedling left after 5 seeds I germinated, and I would love to use him as a control plant with my good strains when they get here. But I had a jackass with me when I was transplanting, and while I was holding the soil clump he pushed off a big loose piece. It didn't take the main part of the roots, but god only knows how much root damage she took, and how much longer that will stunt my growth. We'll see tomorrow.