For my potted plants, I have always supplemented with an organic liquid fish emulsion/seaweed fertilizer. This is in conjunction with a slow release fertilizer.
This past year, I had two cherimoya's, a Carra Carra, my Parfianka pom, and atulfo mango on the same drip zone as I am establishing these trees. I would water deeply then fill the drip filter reservoir with the fish emulsion/seaweed blend and turn the water back on for 10 minutes to apply the liquid fert to the trees. They respond well and in about a week, you notice the effects.
The only issue i had there was that my largest cherimoya received too hot a mixture and it burned it. Since they are in the ground and more established, I will probably only continue to do this with the seaweed extract.