I have several fig trees in a hot house. Unfortunately several trees have
been infested with ants. The little blighters are in the soil in the pot and
crawling into crevices in the folds of the branches. I've tried immersing
the pots in water, spraying insect spray but to no avail. They just run up
out of the soil carrying their eggs and I can kill lots of them with the
spray but they back a week later just as bad. trees are healthy though.

Any suggestions?

Lee Miles
Tasmania
Australia