I don't know anything about the folk method so I asked Mr. Google who said:
To make a tincture using the folk method, simply fill a jar with the clean plant material of your choice, cover it with the solvent of your choice, in this case 80 to 100 proof vodka (depending on whether you are using dried or fresh herbs), cover the jar, place in a dark, cool cupboard and let it set for a minimum of...
From the little bit that I know about tincture, it seems all the herbs need to be under the liquid. I feel this is more important than the radio.