Fig plant pot become a huge ant nest

[Mung]

My fig tree is currently in my greenhouse (after I hacked it back close to death and felt that a stint of greenhouse rehab might help bring it back to life) and the pot is one huge ant nest. I am not sure what to do with it, as I dont want to put it outside suddenly as it is just starting to look more fig-like again. Even if I were to re-pot it, how would I get all the ants off?

Any suggestions?

I had this with a potted olive tree. Tried ant powder but it didn't work.

Was finally successful by removing it from the pot and washing every last bit of soil from the roots, before repotting.

Made a right mess of the patio though

Should I wait until autumn to do this?

I had similar thing with bay tree in pot. We live next to a river so I took it out of the pot and stood it in the river for a few hours (this was a few months ago - would get washed away now!) Then repotted it but the ants have come back.

Also found a nest in my pot of rocket. Grrrrrr.

Builders dumped a load of scaffolding outside last week. Went to move one of the poles last night and nest under it. The little B***s seem to be everywhere this year. Put anything down for more than 5 minutes and they seem to put a nest under it.

Sorry no helpful advice really

Do you think they will harm the tree if I just leave them there?

They may eventually kill it as their nest consumes all the soil and leaves the roots hanging in mid air.

Probably only solution to try is washing the roots and repotting - and add ant poison to the new soil to prevent reinfestation.