Osmocote Controlled Release Fertilizer
   13-13-13,
   6 to 9 month release (in 70° F soil)
     Osmocote was developed in the 1960s and was one of the earliest time-release or controlled release fertilzers. It is best used for soil-based plants, and releases based on soil temperature.

Full strength is 1/4 tsp. per 1" pot size. Sprinkle it on the top of the soil.
Do be careful though—don’t over fertilize.