As the title says, I am looking for a place to buy some real topsoil in Miami so I can make MTS (mineralized top soil). I have been to Home Depot, Target, KMart, Lowe's, and Walmart to no avail. Also, I Googled garden center, and cannot find one with exactly what we need to make MTS.
Miracle Grow Organic Choice Potting Soil 32 Qt. (dry) bag was $8.00 when I purchased mine at HD.
The Fraternity of Dirt
If at first you don't succeed,,, keep kicking it RubberSideDownOnTheLanding, 2-75g planted, 5-55g planted, 5-20g planted, 110g w/30g sump, 8-10g, Refugium, doghouse/newbie 2012 update adding table top pleco pans & a 90g (Nutz)
Best store in my opinion is Neighborhood fish farm near bird road and 117th ave. They usually have a lot of good plants, and anything they don't have, they will order for you from Florida Aquatic Nurseries. Or if you don't mind a drive Allfish Emporium (6820 N. University Drive Tamarac, Florida 33321) is great.
Most of the bagged "topsoil" products that you see for sale are actually various combinations of peat moss and composted bark with various other ingredients containing little if any actual topsoil. If you mineralize that kind of material you might end up with nothing at all!
You would do much better to get some regular topsoil from somebody's yard or out in the woods somewhere. In your area the topsoil is probably all very sandy. Do you have any reason to go up to northern FL?