@dezroz
Hi, Joe! I just noticed that you have not received a response yet to your inquiry.
I'll give it a shot...I don't foliar feed purposely. Supposedly adenium leaves do not absorb NPK through their leaves. However, I have heard that leaves and seed pods sprayed with a dose of Boron will aid in the development of perfect flowers as well as seed pod development. But I think this is a quick fix that is absorbed by the plant if deficient of this element. Another is Magnesium sprayed on the plant...another quick fix for deficiency of this vitamin.
Plants take up their nutrients from the soil, but I guess they could take up certain minor elements from foliar feeding when needed?
