I'd choose Promix, and I wouldn't add anything to it but fertilizer. The other mixes could cause problems with moisture retention in an Earth Box because of the organic additions. And they are unreliable nutrient sources in any container, so you'd still need to fertilize.

I kind of looks like a melon from Uzbekistan, which I found a picture on this webpage. Look at the picture about 3/4 of the way down with the hanging melons. How did it taste? Dean

I fill my raised beds with free, locally available organic material. Usually the bottom is cardboard (to smother what was already growing there) then perhaps wood chips, old produce, leaves, horse manure, and whatever spare compost or soil from another garden on top. Now that I get so much old produce free, and we cut and burn firewood, I use wood shavings instead of wood chips, and also throw in some ashes for extra calcium and potassium. I started stockpiling other people's leaves in the fall so I always have some of those, and the horse manure is free whenever I want it. I have never asked for coffee grounds, but I had taken home the bag of corn husks from grocery stores a few times before I started getting the large quantities of old produce. Basically seek and ye shall find! In summary, NO NEED TO BUY ANYTHING TO FILL A RAISED BED! I suggest you search lasagna in this forum for lots of info about making lasagna (layered) raised beds. Marcia

I've grown sweet peppers and eggplant together without a problem. Currently I'm growing some green peppers with sugar snap peas. I plan on adding some sweet peppers and basil to that system as well. they'll all be running at a concentration of approximately 650 ppm. I'm not sure how much the green peppers or basil will like that, but I know the peas and the sweet peppers should be fine. I wouldn't grow tomatoes with them though as they're heavy feeders and take a higher concentration (currently 900(-)ppm)