No it would be the average. Those numbers are a percent nitrogen-phosphorus-potassium. Since it is 6% nitrogen in the organic fertilizer, multiply how much 13-13-13 you need by 13/6 or 2.1667. If the number is in the publication is 8-8-8. Substitute 8 for 13. The best way to apply is to get an auger bit for planting bulbs and drill holes around the canopy of the tree. Space the holes about a foot apart and one foot down,fill with the fertilizer mixture then top with soil. If you have any questions let me know. I garden organically as well.
This post was edited on 3/5 at 6:18 pm