fertilizing banyan trees?

[My 2 cents]

A weed is just a plant out of place. In my list of attributes for banyans I neglected to mention that they can also be quite beautiful and majestic. It's possible that you have a place that is suitable for a banyan to exhibit these qualities. I urge you to think it through and consider the work you might be creating for yourself but, having said that, if you do decide to cultivate it then my answer to your original question remains the same. It will gobble up anything you want to feed it, but there is no need to.

Good luck!

[Obie]

I found one in the front 1/3 of my acre in HPP. It was in the middle of a huge mess of guava and junk trees. The roots completely covered the 1/3 acre and were a matted mess almost a foot thick. After clearing it all away the 1/3 acre was bare lava.
It took 6 of us an entire day to cut it down and grind it up. A neighbor had a 14 inch industrial chipper and we turned it into mulch.
I was left with an 8ft tall 4ft diameter stump that I had ripped out of the lava with a D9.
The D9 driver ran over the darn thing for 1/2 hour but it was so fibrous that he couldn't break it up.
The neighbor came back with his stump grinder and turned it into sawdust.

[Olohana 1790]

invasive species... why not try to grow ohia, I live very near you and have hundreds of ohia keikis Ive grown.. they WILL reach 10'+ tall in 5 yrs... just move the logs, rocks, hapus that have tiny keiki on them to a shadier area and watch them take over the log/rock and take off. I have yellow ohia cutting that are now trees 15-20' tall. Ive only had my property in upper Puna for 13 yrs now, and have dozens of endangered species now growing on it. you can do this too, please dont use some plant disease as a malahini excuse to encourage the growth of bad invasive species..
aloha

#1 endangered species capital of World
#1 invasive species capital of World