I'm not going to drag past Directing q/a at the original poster.

But testing soil before you get it home is not going to happen,
neither is buying lots of soil.

Gardens are popular in alot of Asia. outside of big cities Most of them are outside.

Crappy soil is everywhere. If you have ever been to a market in (almost) anywhere in Asia, its good to remember that everyone and their parents sells products. That means a lot of the time, there is a whole more more bad then good of any product you buy, most of which advertise GOOD BEST PURE (etc) anywhere on the product. When you guy PureCoffee, More then likely you're getting *brand*Pure*product*Coffee. I can See mercybeats in a shop looking for soil, and not only finding pure soil, but perfect soil, pro mix, pro mixx, por mix, and anything in between, which is why i gave the default/generic answer of adding something to lighten up the soil. Unless i'm mistaken (i'm a very novice grower) That is advice that will not lead you wrong.