I'm not sure that would help to much but I'd like to hear why you think that.
After work today I noticed more yellowing. I've been watering every 2 days but I might have to step it up to every day. The soil is completely dry and brittle after 2 days. As soon as my HTG order comes in I'll be transplanting them into 2 gal bags..
My wife has several horses, along with quite the pile of horse shit. I plan on mixing the organic soil with the horse shit compost pile when I transplant. Does anyone think a 50/50 mix would be too much?
It really looks like overwatering to me, and Perlite helps the roots get oxygen. Check out the link in my signature for pictures of symptoms. Sorry I can't answer your horse manure question..just never used it.