I am growing 2 bird of paradise from seed. they are about 2 yrs old. I potted them on into bigger pots this Spring and they have grown significantly. I hav noticed that some of the strong roots are growing out the bottom of the pots, tilting the pots. Should I leave them till next Spring again to pot on, or should I pot on again in case the roots become damaged? I would hate to lose them at this stage.