I just found out from reading gwe (I love this site) that you shouldn’t use miracle grow potting soil for cannabis growing for many reasons. The thing is I did and I am now into week 5 of the flowering stage. Should I just leave my ladies alone or is there anything I can do at this stage ( Purple Kush )
Don't believe everything you read about MiracleGro. There is a lot of misinformation. First of all, you have to qualify which specific product. The "MiracleGro Potting Mix" is fairly hot at 0,21-0.11-0.16. That product uses time-release synthetic nutrients. (You nor the plant have a great deal of control over what the plant receives. If it were organic-sources of nutrients, the roots could interact with soil microbes for what it needs.). However, MG "Organic Choice potting mix" is only 0.10-0.05-0.05. That's half as "hot," and comes from organic sources of nutrients (not something that will "release" with each watering.). There are people who use this potting mix to grow in, happy with it, etc.
You said "potting soil." That's another aspect of MG products which is confusing. For example, there is an "Organic Choice potting soil" which is hotter. I don't think "potting soil" is a good choice for growing cannabis. It can compact and be heavier/denser (slow drying, less air to the roots.). I've never used a "potting soil." I don't know for sure. But, I would stay away from it, personally.
There's also an MG Performance Organics potting mix (and potting soil, just to confuse things further). It has an unusual NPK (0.19-0.01-0.01). That seems unbalanced (toward N). But, probably not as problematic as the slow-release synthetic "potting mix."
Anyway, there's nothing inherently wrong with MiracleGro (other than it's owned by Scotts, and people hate Scotts for being affiliated with Monsanto, "big agro." Although Scotts now owns Botanicare, General Hydroponics, Sun Systems, et. al.). Like any brand, some things are more suitable for a task than others.
I haven't used any MiracleGro potting mixes. Although, that high-N "performance organic" would work well with the Kellogg Cactus mix I'm testing right now. It's very deficient in N. If it was mixed with that "performance organic" potting mix ("container mix" is what they call that one), that would probably help. I have grown a plant from seedling to harvest with MiracleGro "Tomato" fertilizer (18-18-21). It came out fine.
I wish we had a MiracleGro-specific forum that could showcase growing with those products, and answer questions intelligently. The forums seem dominated by urban legend. (Even GrowWeedEasy has a couple pages that I question whether they're really informative, or just spreading a meme. "Don't do it!").