I just potted a tree in akadama yesterday. Does akadama have nutrients from the start or would it need to be fertilizedto hold nutrients. I have a lava and clay mix.

Akadama is just volcanic clay. It doesn't provide any particular nutrient per se, although it is said to keep them around for longer and ease their absorption by plants (FWIW, I've always wondered how much that is true...).

That said, if you repotted and did any work to the roots you probably don't want to fertilize immediately, and certainly not with nitrogen-rich fertilizers.

Then when should I start fertilizing it?

When the tree has recovered and are happiliy growing.

When to fertilize is about the same question as how long is a piece of whool. Note that plants do not need fertilizer constantly. Most of what a plants needs to live are light, water and air. Fertilizer provides building block essential for growth, but health plants have good reserves in times of need.