I am regularly asked which eucalyptus species is suitable for indoor use. To be clear, I grow eucalyptus for a cold climate and it is a tree that can grow quite large. Now I see a lot of advice and advertising on the internet and in garden programs claiming that you could also keep eucalyptus indoors. This is also regularly mentioned on the plant label.
My personal opinion on this is that this is absolutely untrue as far as the species (often an “ordinary” gunnii) that are offered. These are sales pitches that ultimately end in disappointment for you as a customer. If you want to keep a eucalyptus indoors, you will eventually have to seek advice from a specialist about which species could possibly be suitable for this and take into account that such a plant requires attention to make this successful.