Growing my seedlings inside since November, I would say it gets more and more challenging to grow them as they get larger.
They can grow inside with stale air and lower humidity. But as they get larger, it gets harder and harder to water them. My main issue seems to be insects and watering too late.
But this is different from taking a bonsai azalea, maybe imported from Japan.
That said though. I often take such plants, imported whips from Japan, and I put them indoors to force them to grow earlier. And that works fine.
But the growth is very tender, though. It grows fast, without air movement, etc.