I'm looking for a loamy soil, possibly even a bit on the sandy side: I need a soil with good drainage.
I'm completely new to gardening though. I took a trip to Calloways today and bought potting soil and sand. The potting soil advertises that it retains moisture, which is not what I wanted; hence why I bought the sand. But the sand seems fine (it's advertised as "Premium Gardening Sand", I don't know if that means it should be fine or coarse), which when I looked online, seemed counter productive towards increasing drainage. Calloway's had Green Sand and Lava Sand, are any of these things good for increasing drainage?
In retrospect, I noticed they had a topsoil. I may go back to see if the topsoil mentions its composition (like 50% sand) which might indicate it has good drainage. There were also small packets of potting soil for cacti, which indicates it may drain well. If I got this, would I need anything else to add on?
For reference, I'm growing Rhodiola Rosea (Can I even make this work in Texas?), and Flax (Which probably doesn't need much more than just potting soil) at the moment.