Steve wrote:

Hi,
Is potassium nitrate still used? I thought it was an ingredient in "poor
man's daily dosing drops".
Steve

Yup, you can either get it at a local garden store, from
www.gregwatson.com, or sometimes as stump remover (check the label).

KNO3 ("Nitrate of potash" or "saltpeter") adds both potassium and
bio-availible Nitrogen (as nitrate).