younghelleboreplantsshouldbegrownonindoorsuntilwhathight?

if they are in pots then they can go in any time but now is a good time as they will settle while the soil is still warm.
welcome to GoY too.
could you also put spaces in between your words. It took me ages to work out what you were asking :o)

Ditto - you need to use the space bar at the bottom of the keyboard, if you don't know where it is;-))

The space bar is the long blank bar on the bottom centre of your keyboard ;-)

Just a cautionary note - there's another question posted today on tiny Hellebore plants which are really only plug-plants. If yours are as tiny, you will need to pot them on and let the rootballs grow bigger before you plant them out. I would personally keep mine in the coldframe over the winter, as that sized plants are NOT going to flower next spring.