It's not too acidic. Growing in containers is different than growing in the ground. The plants will feed from the nutrients in water you give them which will have a higher pH than the mix. Growing in containers with the 511 mix is more akin to hydroponics.

I grow a monster Sun Gold in a 15-gallon container on the back deck every Summer (for the past 4 years). 5-1-1 with Osmocote, sometimes Fish Emulsion, sometimes Foliage Pro. This year's plant is already off to a great start.

Yeah, forgot to refer to your original concern about Tomatoes. I and others grow plenty of tomato plants in 511 with no problem.

I'm in my third year of using the 5-1-1, Osmocote, Foliage Pro routine on my tomatoes, and I couldn't be happier. I grew them in a combination of ProMix and compost for many years before that, and had more problems with soggy soil and disease than I do now. Here are some of my plants from July 1, 2012, in 25-gallon Smart Pots with Texas Tomato Cages. Best year ever.

{{gwi:30693}}

tomatoes mmmmmmm they are the best :) keep showing the pic's guys I need motivation to get through winter.

hey look these were grown in 5" of cow poo LOL pulled that garden up going to grow pots on there this spring see how they do ? they got like 10 foot high.

BZ