I recently moved to a house with 4 very large royal palms. Probably 30 feet or more. The root flare is showing on all of them. I know that's not necessarily a bad thing but I wanted to know if I could bring the soil level up on them without damage. The yard/gardens need work and I'd like to add a lot more compost and manure when I put in bananas, papaya, lemongrass, dragon fruit, aloe...a typical tropical edible mix for a small yard.

Also, could growing dragon fruit, or philodendrons damage the trees? They already have a decent amount of lichens and airplants.