Q. My mother sent me one of your newspaper columns over 20 years ago. It had a recipe for plant food that I have used successfully for years.
Now I cannot find a key ingredient, saltpeter, except as a tree stump remover. I don’t need that much. Where can I order saltpeter like I used to, 6 to 8 ounces at a time?
A. A retired journalist shared the Pantry Plant Food recipe from the Georgia Market Bulletin many decades ago. It called for “one teaspoon (tsp) baking powder, one tsp Epsom salts, one tsp saltpeter, one-half tsp household ammonia, all stirred into one gallon of warm water. Warning: do not use more often than monthly or the leafy plants will crowd you out and the flowering ones will bloom themselves to death.”
Some people looking for saltpeter (potassium nitrate) to use in this recipe had to deal with the embarrassing perception that they planned to use it to cool a partner’s romantic ardor. Although it has a reputation for that, there is no evidence saltpeter works to diminish libido.
Saltpeter can be used, however, to make explosives, and that probably accounts for the fact that it is nearly impossible to purchase it in bulk. We were unable to find any source except, as you noted, labeled for tree stump removal.