Houseplants need less fertilizer than outdoor plants and my experience shows you don't need to be exact with the product as long as you keep in mind that less soil means less fertilizer. So for a small 4 or 5 inch pot just use a pinch of Osmocote or 1/8 of a teaspoon. Twice this much for a container that holds twice as much soil. Work the granules gently into the top inch of soil and water when soil is dry. It helps to think of a gallon of milk and how this would fill a gallon size pot. So a pot that would hold only a quart of milk would need 1/4 of a tablespoon as there are 4 quarts in a gallon, and the recommended rate for indoor plants is about  one tablespoon for a gallon container.  (Remember that indoor plants use half the recommended rate as outdoor plants.) If your houseplant is one that blooms or you want faster growth use a bit more. The product works slowly so there is less danger of fertilizer burn from using too much. Apply once or twice a year. I love the value of this product because a little goes a long way and you can use if for years as long as you keep the granules dry and in a cool location. Keep growing, Marianne Binetti